Suspected crankcase position sensor failure
Thread Starter
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Junior Member
Joined: Apr 2023
Posts: 17
Suspected crankcase position sensor failure
Sorry for the long read but the more "seat of the pants" you have the better.
Me and my high mile 1998 SL sedan 4 banger with a manual trans were doing 75 - 80 mph on the freeway after about 15 miles of city driving and all is normal, including temp & oil read. I'm not sure which I noticed 1st but I think I felt something that made me look at the dash before I noticed the tach as it was dropping from 4K and headed for zero fast, then at about 1K while it was still in gear, and still doing 65 to 70. It popped back up to high 3K's but then back down to 2K rpm or so and back up and now we are definitely going slower. It's before sunup and the dash lights are on and staying on. They didn't follow the tach's dance but that dance along with the car's 40,000 mile trouble free one were over and the tach is staying at zero. The 1st thing I notice besides there's no shoulder is the temp looks normal and everything smells normal too. The car's starting to slow down for real now so I push the clutch in but there's no way in hell the zero rpm indicated was correct. Then I see a decent shoulder right after an entrance ramp and duck in there. I'm not sure about the car but my fear of us getting hit in the *** got a lot better. "Twenty minutes later" doesn't quite cut it, but what transpired next is I tried to start it and the starter turned the engine but it sucked, there was no boom bang to the car's song anymore. Not wanting to run the battery down I stop trying to start it. After about 15 minutes of calls, the last one being to my brother the mechanic again. I got under the car and tapped the bottom of the gas tank with a tool. I don't think that had anything to do with it other than the time transpired but this time when I tried to start the engine it did and it sounded normal, idle was normal too. There was an overpass incline ahead as the shoulder closed out again so I took off a little heavy on the throttle and it died hard. Most of that "hard" is because it was in 1st gear and I was slow to push the clutch in. Another half hour goes by and now there's a cop behind us. Not that either of us are cop lovers but I'm sure the car's less worried about taking an 18 wheeler up the ***. And the officer is telling me getting towed off the highway is free. Word to the wise folks, whether you have AAA or not. If your car craps out at speed on the highway (in Houston anyway) put it in neutral ASAP and get it as far out of traffic as possible. Risking stopping traffic to make it to an exit is the wrong move. Remember it this way. It's called a feeder road for more than one reason.
Now towed into a Hoe Depot parking lot. I chose to feed the wrecker $208.00 for the tow home. (front wheel lift 30 miles) I don't think that ride changed any loose wire problem but it's possible? Then 2 hours after the fact and off the wrecker, it starts and operates the same as it ever did except it had a 2000 rpm that only came down to 1000. It had a very similar problem before when I bought it but that time is was idling at 2000 or so and staying there. That prob was fixed years ago by changing a MAP sensor and that replacement reads GM on it. I don't want to risk another $200.00 towing pop till I swap some parts. That one sure a hell is a lot easier to get at but It's got zero to do with reading the rpm.
Questions:
I lost where I read it so where is the rpm signal generated from?
What is the most likely cause other than the CPS?
Me and my high mile 1998 SL sedan 4 banger with a manual trans were doing 75 - 80 mph on the freeway after about 15 miles of city driving and all is normal, including temp & oil read. I'm not sure which I noticed 1st but I think I felt something that made me look at the dash before I noticed the tach as it was dropping from 4K and headed for zero fast, then at about 1K while it was still in gear, and still doing 65 to 70. It popped back up to high 3K's but then back down to 2K rpm or so and back up and now we are definitely going slower. It's before sunup and the dash lights are on and staying on. They didn't follow the tach's dance but that dance along with the car's 40,000 mile trouble free one were over and the tach is staying at zero. The 1st thing I notice besides there's no shoulder is the temp looks normal and everything smells normal too. The car's starting to slow down for real now so I push the clutch in but there's no way in hell the zero rpm indicated was correct. Then I see a decent shoulder right after an entrance ramp and duck in there. I'm not sure about the car but my fear of us getting hit in the *** got a lot better. "Twenty minutes later" doesn't quite cut it, but what transpired next is I tried to start it and the starter turned the engine but it sucked, there was no boom bang to the car's song anymore. Not wanting to run the battery down I stop trying to start it. After about 15 minutes of calls, the last one being to my brother the mechanic again. I got under the car and tapped the bottom of the gas tank with a tool. I don't think that had anything to do with it other than the time transpired but this time when I tried to start the engine it did and it sounded normal, idle was normal too. There was an overpass incline ahead as the shoulder closed out again so I took off a little heavy on the throttle and it died hard. Most of that "hard" is because it was in 1st gear and I was slow to push the clutch in. Another half hour goes by and now there's a cop behind us. Not that either of us are cop lovers but I'm sure the car's less worried about taking an 18 wheeler up the ***. And the officer is telling me getting towed off the highway is free. Word to the wise folks, whether you have AAA or not. If your car craps out at speed on the highway (in Houston anyway) put it in neutral ASAP and get it as far out of traffic as possible. Risking stopping traffic to make it to an exit is the wrong move. Remember it this way. It's called a feeder road for more than one reason.
Now towed into a Hoe Depot parking lot. I chose to feed the wrecker $208.00 for the tow home. (front wheel lift 30 miles) I don't think that ride changed any loose wire problem but it's possible? Then 2 hours after the fact and off the wrecker, it starts and operates the same as it ever did except it had a 2000 rpm that only came down to 1000. It had a very similar problem before when I bought it but that time is was idling at 2000 or so and staying there. That prob was fixed years ago by changing a MAP sensor and that replacement reads GM on it. I don't want to risk another $200.00 towing pop till I swap some parts. That one sure a hell is a lot easier to get at but It's got zero to do with reading the rpm.
Questions:
I lost where I read it so where is the rpm signal generated from?
What is the most likely cause other than the CPS?
Thread Starter
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Junior Member
Joined: Apr 2023
Posts: 17
Sorry for the screw up who's ever it was. Here AGAIN is my attempted new member post.
Dark green SL1 sedan with 234K miles. I've owned mine since 2013. Yes 2013, the reason I've never opened my yap here before is I've never had a problem I couldn't fix but relax. This isn't the section for that anyway. As for the "me & mine" crapola. Mine is a suspected crankshaft position sensor. Oh wait I meant, mine also has a SOHC 1.9 with manual transmission.
I didn't realize my kid was too cool for it when I bought this garage kept gem but I tell you what. I'm damn glad, because that car has been the best $800.00 I've ever spent on a vehicle. High miles or not and now that we've gone another 40,000 miles together. I can honestly say I'm hoping to make people wonder what the hell that old man is grinning so bad about when it hits 300K. There's no "Belly up" section" so please look for me in the "general tech help" section shortly.
PS. That "belly up" is not about the car. That's about getting on that crawler again to make one of those so-called cheap car payments.
Dark green SL1 sedan with 234K miles. I've owned mine since 2013. Yes 2013, the reason I've never opened my yap here before is I've never had a problem I couldn't fix but relax. This isn't the section for that anyway. As for the "me & mine" crapola. Mine is a suspected crankshaft position sensor. Oh wait I meant, mine also has a SOHC 1.9 with manual transmission.
I didn't realize my kid was too cool for it when I bought this garage kept gem but I tell you what. I'm damn glad, because that car has been the best $800.00 I've ever spent on a vehicle. High miles or not and now that we've gone another 40,000 miles together. I can honestly say I'm hoping to make people wonder what the hell that old man is grinning so bad about when it hits 300K. There's no "Belly up" section" so please look for me in the "general tech help" section shortly.
PS. That "belly up" is not about the car. That's about getting on that crawler again to make one of those so-called cheap car payments.
Super Moderator
Joined: Jul 2005
Posts: 12,316
From: Slightly off center
Hi.
Your welcome post got hung up in our spam filter. It is now free.
How many total mi on
1) the vehicle
2) the engine
3) the trans
4) the fuel pump
5) the clutch plate and master slave cylinder.
6) fuel filter
7) catcon
Trying to get an overall idea of what the car is in terms of age and use. Not saying all of these things are necessarily involved, just things I'd want to know before I start troubleshooting.
More in a second
Your welcome post got hung up in our spam filter. It is now free.
How many total mi on
1) the vehicle
2) the engine
3) the trans
4) the fuel pump
5) the clutch plate and master slave cylinder.
6) fuel filter
7) catcon
Trying to get an overall idea of what the car is in terms of age and use. Not saying all of these things are necessarily involved, just things I'd want to know before I start troubleshooting.
More in a second
Super Moderator
Joined: Jul 2005
Posts: 12,316
From: Slightly off center
Crap my reply just got erased.
1) when the tach was dancing around, were these smooth movements or quick jerking movements? Could you feel the RPMs change in the seat of your pants or hear them change? This is critical to know because we need to determine whether this is an engine behavior or a sensor issue.
2) you said the dash lights were on and staying on but not following the tach, and by then, the tach read zero. Are you referring to the idiot lights that come on when you turn the key to on but don't crank the engine? These lights turning on with the tach at 0 are consistent with an engine stall.
3) you coast to a stop, wait, car cranks. Did you hear it fire or was it absolutely just spinning? This is another critical part of the troubleshooting.
4) time passes, you rap on the gas tank then the vehicle starts and seemingly runs normally. I'm thinking your mechanic friend may have thought something was blocking the screen at the bottom of the fuel pump where the fuel is taken in by the pump. Maybe thumping on it dislodged something, maybe it did absolutely nothing. Unclear. What was the gas gauge reading in the vehicle at the time?
5) car is running and idling fine, you take off in first, have your foot into it going to higher RPMs, but it falls flat on its face and stalls. Does it do another RPM dance or does it just cut off or does it slowly lose life and then stall? This is also critical to know.
The crank position sensor CKP, when it fails, cuts both spark and fuel injectors. It does us because the PCM no longer knows where the crank is in its rotation so it doesn't want plugs firing with the pistons who knows where in their travel.
CKP failure on s cars usually transpires in one of the following ways:
A) you drive to the grocery store do to your shopping. You come out, load your groceries, turn the key and crank, but the car won't start. If you listen carefully, the engine is not firing either. In this case, the CKP coil has a break in it and fully separates so there is no CKP signal to the PCM. Bye-bye fuel bye-bye spark. The number of heat cycles that sensor is subjected to is quite high so it's not unexpected that eventually the little coil in there will develop a break.
B) the other mode of failure is usually observed when you are driving around the neighborhood and your car stalls on a dime for no reason whatsoever. If you wait 20 minutes, starts back up like nothing ever happened. This keeps repeating, pissing you off to no end.
What do these have in common? Heat. In B there is also a break in the coil, but when it cools down it reestablishes contact at the break and the circuit becomes continuous again. So while you are driving around, everything is heating up and when it gets hot enough the coil expands and becomes discontinuous and the car stalls. Wait long enough for it to cool down, and it behaves normally.
One thing is for certain. When the CKP goes open circuit to the PCM, you have no fuel and no spark, and the engine stalls. I would not expect an RPM dance on the way to silence, but since you had it in gear, the wheels were still engaged to the trans which was still in gear and therefore was rotating the engine, kind of like an engine braking situation.
I have to go look it up but I believe the vehicle speed sensor and the transmission speed sensor are both on the transmission. 1 is on the input shaft and the other is on the output shaft but I haven't looked at that in probably 8 years so I'll get back to you. You didn't mention anything about the speedometer behaving oddly. This would lead me to believe that the speed sensor is not an issue.
-------
Is your service engine soon light on? If it is, please stop by AutoZone or similar and have them read the codes or have your brother read the codes and post them here as Pxxxx not the names of the codes. This should give us a head start on troubleshooting.
Have you ever cleaned the EGR valve on this vehicle? I know you purchased it used. Can you tell if it is a Saturn/GM OEM or aftermarket part by the stampings on it?
Have you ever changed the fuel filter on this vehicle? Pretty sure 98 is accessible.
Please take the time to answer each of the questions. I know there are a lot of them but without getting all the cards out on the table at once, this will become a guessing game and that gets expensive and frustrating. We don't shotgun parts, we diagnose only the bad ones and we all learn something new about s cars.
1) when the tach was dancing around, were these smooth movements or quick jerking movements? Could you feel the RPMs change in the seat of your pants or hear them change? This is critical to know because we need to determine whether this is an engine behavior or a sensor issue.
2) you said the dash lights were on and staying on but not following the tach, and by then, the tach read zero. Are you referring to the idiot lights that come on when you turn the key to on but don't crank the engine? These lights turning on with the tach at 0 are consistent with an engine stall.
3) you coast to a stop, wait, car cranks. Did you hear it fire or was it absolutely just spinning? This is another critical part of the troubleshooting.
4) time passes, you rap on the gas tank then the vehicle starts and seemingly runs normally. I'm thinking your mechanic friend may have thought something was blocking the screen at the bottom of the fuel pump where the fuel is taken in by the pump. Maybe thumping on it dislodged something, maybe it did absolutely nothing. Unclear. What was the gas gauge reading in the vehicle at the time?
5) car is running and idling fine, you take off in first, have your foot into it going to higher RPMs, but it falls flat on its face and stalls. Does it do another RPM dance or does it just cut off or does it slowly lose life and then stall? This is also critical to know.
The crank position sensor CKP, when it fails, cuts both spark and fuel injectors. It does us because the PCM no longer knows where the crank is in its rotation so it doesn't want plugs firing with the pistons who knows where in their travel.
CKP failure on s cars usually transpires in one of the following ways:
A) you drive to the grocery store do to your shopping. You come out, load your groceries, turn the key and crank, but the car won't start. If you listen carefully, the engine is not firing either. In this case, the CKP coil has a break in it and fully separates so there is no CKP signal to the PCM. Bye-bye fuel bye-bye spark. The number of heat cycles that sensor is subjected to is quite high so it's not unexpected that eventually the little coil in there will develop a break.
B) the other mode of failure is usually observed when you are driving around the neighborhood and your car stalls on a dime for no reason whatsoever. If you wait 20 minutes, starts back up like nothing ever happened. This keeps repeating, pissing you off to no end.
What do these have in common? Heat. In B there is also a break in the coil, but when it cools down it reestablishes contact at the break and the circuit becomes continuous again. So while you are driving around, everything is heating up and when it gets hot enough the coil expands and becomes discontinuous and the car stalls. Wait long enough for it to cool down, and it behaves normally.
One thing is for certain. When the CKP goes open circuit to the PCM, you have no fuel and no spark, and the engine stalls. I would not expect an RPM dance on the way to silence, but since you had it in gear, the wheels were still engaged to the trans which was still in gear and therefore was rotating the engine, kind of like an engine braking situation.
I have to go look it up but I believe the vehicle speed sensor and the transmission speed sensor are both on the transmission. 1 is on the input shaft and the other is on the output shaft but I haven't looked at that in probably 8 years so I'll get back to you. You didn't mention anything about the speedometer behaving oddly. This would lead me to believe that the speed sensor is not an issue.
-------
Is your service engine soon light on? If it is, please stop by AutoZone or similar and have them read the codes or have your brother read the codes and post them here as Pxxxx not the names of the codes. This should give us a head start on troubleshooting.
Have you ever cleaned the EGR valve on this vehicle? I know you purchased it used. Can you tell if it is a Saturn/GM OEM or aftermarket part by the stampings on it?
Have you ever changed the fuel filter on this vehicle? Pretty sure 98 is accessible.
Please take the time to answer each of the questions. I know there are a lot of them but without getting all the cards out on the table at once, this will become a guessing game and that gets expensive and frustrating. We don't shotgun parts, we diagnose only the bad ones and we all learn something new about s cars.
Last edited by derf; Apr 20, 2023 at 05:31 AM.
Thread Starter
|
Junior Member
Joined: Apr 2023
Posts: 17
Thanks for the in depth response!
I'm all for blaming my internet probs on your spam filter but I'm pretty computer challenged myself.
I won't be responding fast but it's all good, I'm not morally challenged and will always respond.
Total miles on car 234,000
1) the vehicle SL1 4 dr
2) the engine SOHC 1.9
3) the trans Manual
4) the fuel pump Unknown assumed to be stock.
5) the clutch plate and master slave cylinder. Too good to be stock? But also unknown, vehicle was acquired with 190,000 miles on it
6) fuel filter unknown
7) catcon The exhaust is completely stock.
1) when the tach was dancing around, were these smooth movements or quick jerking movements? I'd have to say quick jerking movements. Could you feel the RPMs change in the seat of your pants or hear them change? No, I didn't feel the RPM change immediately anyway while in 5th gear going 75 or better.This is critical to know because we need to determine whether this is an engine behavior or a sensor issue.
That rpm dance was a very short one but I'm certain I saw it go down and back up at least once. There was more than one rapid drop from an actual believable engine rpm reading. Once the tach went to reading absolute zero it did not come back up again clutch in or out while still in 5th gear.
2) You said the dash lights were on and staying on but not following the tach, and by then, the tach read zero. Are you referring to the idiot lights that come on when you turn the key to on but don't crank the engine? These lights turning on with the tach at 0 are consistent with an engine stall.
I believe the 1st time I saw the idiot lights was after the vehicle stopped and I turned the key off? But it was driving like the engine was no longer running. The car does not have power steering. The dash lights I referred to staying on are the ones that come on with the headlights. Those stayed on the entire time and didn't fluctuate like the tach.
3) you coast to a stop, wait, car cranks. Did you hear it fire or was it absolutely just spinning? This is another critical part of the troubleshooting.
I costed to a stop and immediately tried to start it. The starter turned the engine but the combustion cycle wasn't completing. Hate to say it but another reason I like that car so much is all I have to do to fix the noisy dash is turn my hearing aids all the way down.
I can't honestly say there wasn't at least one stumble but it didn't catch enough of a spark to feel through the body of the car after 3 or 4 attempts and approx 30 seconds.
4) time passes, you rap on the gas tank then the vehicle starts and seemingly runs normally. I'm thinking your mechanic friend may have thought something was blocking the screen at the bottom of the fuel pump where the fuel is taken in by the pump. Maybe thumping on it dislodged something, maybe it did absolutely nothing. Unclear. What was the gas gauge reading in the vehicle at the time?
Then after 15 to twenty minutes. Final act being to tape on the bottom of the fuel tank near where I expect the fuel pump is. It started. Motive there was to dislodge any possible problem in the fuel pumps brushes I think? Fuel level was over a 1/4 tank.
5) Car is running and idling fine, you take off in first Have your foot into it going to higher RPMs, but it falls flat on its face and stalls. Does it do another RPM dance Nodoes it just cut off Yes or does it slowly lose life and then stall?No This is also critical to know.
It was idling fine at normal idle speed. Then I suppose I was riding the clutch just a bit because the car had moved forward approx 5 feet but right as I let the clutch all the way out is when it died as I pushed the clutch back in.
The crank position sensor CKP, when it fails, cuts both spark and fuel injectors. It does because the PCM no longer knows where the crank is in its rotation so it doesn't want plugs firing with the pistons who knows where in their travel.
CKP failure on s cars usually transpires in one of the following ways:
A) you drive to the grocery store, do your shopping. You come out, load your groceries, turn the key and crank, but the car won't start. If you listen carefully, the engine is not firing either. In this case, the CKP coil has a break in it and fully separates so there is no CKP signal to the PCM. Bye-bye fuel bye-bye spark. The number of heat cycles that sensor is subjected to is quite high so it's not unexpected that eventually the little coil in there will develop a break.
B) the other mode of failure is usually observed when you are driving around the neighborhood and your car stalls on a dime for no reason whatsoever. If you wait 20 minutes, it starts back up like nothing ever happened. This keeps repeating, pissing you off to no end. And would more than likely cause another tow job! Yes, that does rhyme with another job. Not to brag, but I can still say I've never had to pay for one of those at least.
What do these have in common? Heat. In B there is also a break in the coil, but when it cools down it reestablishes contact at the break and the circuit becomes continuous again. So while you are driving around, everything is heating up and when it gets hot enough the coil expands and becomes discontinuous and the car stalls. Wait long enough for it to cool down, and it behaves normally.
One thing is for certain. When the CKP goes open circuit to the PCM, you have no fuel and no spark, and the engine stalls. I would not expect an RPM dance on the way to silence, but since you had it in gear, the wheels were still engaged to the trans which was still in gear and therefore was rotating the engine, kind of like an engine braking situation.
I have to go look it up but I believe the vehicle speed sensor and the transmission speed sensor are both on the transmission. 1 is on the input shaft and the other is on the output shaft but I haven't looked at that in probably 8 years so I'll get back to you. You didn't mention anything about the speedometer behaving oddly. This would lead me to believe that the speed sensor is not an issue.
The speedometer stayed consistent with the speed of the car through the entire event. That's for certain.
-------
Is your service engine soon light on? If it is, please stop by AutoZone or similar and have them read the codes or have your brother read the codes and post them here as Pxxxx not the names of the codes. This should give us a head start on troubleshooting.
I believe there was a service engine soon light on and I do have a code reader but I still have the battery out. I discovered the breather tube for the trans had cracked under the battery tray. Car payment, car repayment. It's all how you want to look at it. I plan is to buy that before I put that part of it back together.
Have you ever cleaned the EGR valve on this vehicle? No. I know you purchased it used. Can you tell if it is a Saturn/GM OEM or aftermarket part by the stampings on it? No not exactly. I'm saying the ERG is original or at least OEM.
Have you ever changed the fuel filter on this vehicle? Pretty sure 98 is accessible. I have never changed the fuel filter
Please take the time to answer each of the questions. I know there are a lot of them but without getting all the cards out on the table at once, this will become a guessing game and that gets expensive and frustrating. We don't shotgun parts, we diagnose only the bad ones and we all learn something new about s cars.
OTHER INFO: I've started the car and have run it up and down the street one time.
The CPS is nowhere as easy to get to as the EGR but I'm fine with the price. The biggest scare about the CPS is the build quality. I've been through enough Doorman parts on my silverado that I try to avoid doing that as much as possible. Since I have a tow strap and a truck. I guess the 1st thing regardless of the parts replacements it to rig up a good tow strap connection.
I'm all for blaming my internet probs on your spam filter but I'm pretty computer challenged myself.
I won't be responding fast but it's all good, I'm not morally challenged and will always respond.
Total miles on car 234,000
1) the vehicle SL1 4 dr
2) the engine SOHC 1.9
3) the trans Manual
4) the fuel pump Unknown assumed to be stock.
5) the clutch plate and master slave cylinder. Too good to be stock? But also unknown, vehicle was acquired with 190,000 miles on it
6) fuel filter unknown
7) catcon The exhaust is completely stock.
1) when the tach was dancing around, were these smooth movements or quick jerking movements? I'd have to say quick jerking movements. Could you feel the RPMs change in the seat of your pants or hear them change? No, I didn't feel the RPM change immediately anyway while in 5th gear going 75 or better.This is critical to know because we need to determine whether this is an engine behavior or a sensor issue.
That rpm dance was a very short one but I'm certain I saw it go down and back up at least once. There was more than one rapid drop from an actual believable engine rpm reading. Once the tach went to reading absolute zero it did not come back up again clutch in or out while still in 5th gear.
2) You said the dash lights were on and staying on but not following the tach, and by then, the tach read zero. Are you referring to the idiot lights that come on when you turn the key to on but don't crank the engine? These lights turning on with the tach at 0 are consistent with an engine stall.
I believe the 1st time I saw the idiot lights was after the vehicle stopped and I turned the key off? But it was driving like the engine was no longer running. The car does not have power steering. The dash lights I referred to staying on are the ones that come on with the headlights. Those stayed on the entire time and didn't fluctuate like the tach.
3) you coast to a stop, wait, car cranks. Did you hear it fire or was it absolutely just spinning? This is another critical part of the troubleshooting.
I costed to a stop and immediately tried to start it. The starter turned the engine but the combustion cycle wasn't completing. Hate to say it but another reason I like that car so much is all I have to do to fix the noisy dash is turn my hearing aids all the way down.
I can't honestly say there wasn't at least one stumble but it didn't catch enough of a spark to feel through the body of the car after 3 or 4 attempts and approx 30 seconds.
4) time passes, you rap on the gas tank then the vehicle starts and seemingly runs normally. I'm thinking your mechanic friend may have thought something was blocking the screen at the bottom of the fuel pump where the fuel is taken in by the pump. Maybe thumping on it dislodged something, maybe it did absolutely nothing. Unclear. What was the gas gauge reading in the vehicle at the time?
Then after 15 to twenty minutes. Final act being to tape on the bottom of the fuel tank near where I expect the fuel pump is. It started. Motive there was to dislodge any possible problem in the fuel pumps brushes I think? Fuel level was over a 1/4 tank.
5) Car is running and idling fine, you take off in first Have your foot into it going to higher RPMs, but it falls flat on its face and stalls. Does it do another RPM dance Nodoes it just cut off Yes or does it slowly lose life and then stall?No This is also critical to know.
It was idling fine at normal idle speed. Then I suppose I was riding the clutch just a bit because the car had moved forward approx 5 feet but right as I let the clutch all the way out is when it died as I pushed the clutch back in.
The crank position sensor CKP, when it fails, cuts both spark and fuel injectors. It does because the PCM no longer knows where the crank is in its rotation so it doesn't want plugs firing with the pistons who knows where in their travel.
CKP failure on s cars usually transpires in one of the following ways:
A) you drive to the grocery store, do your shopping. You come out, load your groceries, turn the key and crank, but the car won't start. If you listen carefully, the engine is not firing either. In this case, the CKP coil has a break in it and fully separates so there is no CKP signal to the PCM. Bye-bye fuel bye-bye spark. The number of heat cycles that sensor is subjected to is quite high so it's not unexpected that eventually the little coil in there will develop a break.
B) the other mode of failure is usually observed when you are driving around the neighborhood and your car stalls on a dime for no reason whatsoever. If you wait 20 minutes, it starts back up like nothing ever happened. This keeps repeating, pissing you off to no end. And would more than likely cause another tow job! Yes, that does rhyme with another job. Not to brag, but I can still say I've never had to pay for one of those at least.
What do these have in common? Heat. In B there is also a break in the coil, but when it cools down it reestablishes contact at the break and the circuit becomes continuous again. So while you are driving around, everything is heating up and when it gets hot enough the coil expands and becomes discontinuous and the car stalls. Wait long enough for it to cool down, and it behaves normally.
One thing is for certain. When the CKP goes open circuit to the PCM, you have no fuel and no spark, and the engine stalls. I would not expect an RPM dance on the way to silence, but since you had it in gear, the wheels were still engaged to the trans which was still in gear and therefore was rotating the engine, kind of like an engine braking situation.
I have to go look it up but I believe the vehicle speed sensor and the transmission speed sensor are both on the transmission. 1 is on the input shaft and the other is on the output shaft but I haven't looked at that in probably 8 years so I'll get back to you. You didn't mention anything about the speedometer behaving oddly. This would lead me to believe that the speed sensor is not an issue.
The speedometer stayed consistent with the speed of the car through the entire event. That's for certain.
-------
Is your service engine soon light on? If it is, please stop by AutoZone or similar and have them read the codes or have your brother read the codes and post them here as Pxxxx not the names of the codes. This should give us a head start on troubleshooting.
I believe there was a service engine soon light on and I do have a code reader but I still have the battery out. I discovered the breather tube for the trans had cracked under the battery tray. Car payment, car repayment. It's all how you want to look at it. I plan is to buy that before I put that part of it back together.
Have you ever cleaned the EGR valve on this vehicle? No. I know you purchased it used. Can you tell if it is a Saturn/GM OEM or aftermarket part by the stampings on it? No not exactly. I'm saying the ERG is original or at least OEM.
Have you ever changed the fuel filter on this vehicle? Pretty sure 98 is accessible. I have never changed the fuel filter
Please take the time to answer each of the questions. I know there are a lot of them but without getting all the cards out on the table at once, this will become a guessing game and that gets expensive and frustrating. We don't shotgun parts, we diagnose only the bad ones and we all learn something new about s cars.
OTHER INFO: I've started the car and have run it up and down the street one time.
The CPS is nowhere as easy to get to as the EGR but I'm fine with the price. The biggest scare about the CPS is the build quality. I've been through enough Doorman parts on my silverado that I try to avoid doing that as much as possible. Since I have a tow strap and a truck. I guess the 1st thing regardless of the parts replacements it to rig up a good tow strap connection.
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Please hook the battery up, read the codes, and post them here. It is the best place to start troubleshooting. Thank you for answering it on the larger volume of questions. It gives us a baseline.
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Thanks Derf I meant no disrespect of your time with my hunt and peck reply to your answer and appreciate your knowledge shared here.
It looks like my Saturn has another problem symptom since it's dying on the highway episode but it's no worry? That problem is when it has been started now it has a super high idle (2200 rpm) that comes down like it's being poorly controlled by the choke but when it finally goes down it only goes down to 1000 - 900.
It used to idle super high when I bought it 10 years ago. But back then I remember it as staying towards the ridiculously high side of that rpm wrong. That was fixed back then by replacing the Idle air control valve.
Now with a drive around the neighborhood several times. It had the suspected Crankshaft position sensor failure again. This time that was a great failure, almost perfect. It died while accelerating out of 1st gear within an 8th of a mile from the house and pointed towards it. No idiot lights on this time either, the car coasts till it stops. Then with no highway traffic to obstruct what I was hearing or shaking the car. I try to start it but get absolutely nothing, not even an attempted fart. The battery had plenty left when I decided to get out and push too. PS folks, make sure you have shoes on before you take any maypop test drives. The CPS still hasn't been delivered yet but thanks to the input here and the duplicate failure. I'm I'm almost certain replacing the CPS is the right move.
As for the high idle prob. I think I'm only a throttle body cleaning, and possibly an idle air valve replacement away from fixing that too. Yes along with a good EGR cleaning while I'm in there. Thanks again..
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It looks like my Saturn has another problem symptom since it's dying on the highway episode but it's no worry? That problem is when it has been started now it has a super high idle (2200 rpm) that comes down like it's being poorly controlled by the choke but when it finally goes down it only goes down to 1000 - 900.
It used to idle super high when I bought it 10 years ago. But back then I remember it as staying towards the ridiculously high side of that rpm wrong. That was fixed back then by replacing the Idle air control valve.
Now with a drive around the neighborhood several times. It had the suspected Crankshaft position sensor failure again. This time that was a great failure, almost perfect. It died while accelerating out of 1st gear within an 8th of a mile from the house and pointed towards it. No idiot lights on this time either, the car coasts till it stops. Then with no highway traffic to obstruct what I was hearing or shaking the car. I try to start it but get absolutely nothing, not even an attempted fart. The battery had plenty left when I decided to get out and push too. PS folks, make sure you have shoes on before you take any maypop test drives. The CPS still hasn't been delivered yet but thanks to the input here and the duplicate failure. I'm I'm almost certain replacing the CPS is the right move.
As for the high idle prob. I think I'm only a throttle body cleaning, and possibly an idle air valve replacement away from fixing that too. Yes along with a good EGR cleaning while I'm in there. Thanks again..
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