- 93 saturn sl2 [ 4 speed auto]Vin '7'
i drove the car from Vegas up here to the bay area about a month ago, there was 0 problems untill I hit paso-robles, filled up on gas to finish the trip, got on the road. The second I slowed down to the stop light it stalled. Pushed it over into the divider to check stuff, oil was low but not empty, I eventually got it running again like. 3 hours again after many crank no starts, and some starts but stalls within 5/10 minutes. It ended up getting from paso to the exit of salinas no problems [about 60-70 miles.] Again the second I slowed down it stalled. It started up right after to finish driving but ive been having problems ever sense. Its not dependant on heat really. And its not hesitant on power when I give it gas

Ive changed the PCV valve. The MAP sensor, ive checked the throttle pully line. Took the air intake off and made sure the plate wasnt clogged for the throttle. Ive cleaned the idle air intake solenoid. I changed the EGR valve. All my fluids are right

The car is pulling codes 19[non hard code. Came up twice], 26, and 81. 26 being the code for EGR/TPS/IAC, all wich i checked and cleaned. Even went as far as to change the ECU [it is flashed to my car] Ive even towed it to a mechanic. They had it running for an hour. Turned it off. Right back on, for another 30 minutes. The second we pull up to the shop to pick it up is the second it died. Im out of ideas at this point.

 

derf is more knowledgeable about these cars than most of the rest of us here, so he may have better input. Seems that the EGR is a known trouble maker on the 1.9. For some reason, the tube gets full of carbon and not only do you have to clean the EGR but you need to remove and clean the tube also. At least I THINK that's part of what he's explained in the past. Just use the search button here on the forum and type in EGR tube cleaning or something like that. You'll probably find what you're looking for. The worst thing you can do is start shotgunning parts at it and hoping you fix it. That can get expensive and only complicate matters for you. Try this link. It's long but informative. EGR Valve... is it the real culprit?

 

I saw this post. I haven't had a chance to dig through my FSM to help you troubleshoot. But I will in the next few days. Do you have abs or traction control on your vehicle?

 

To my knowledge it doe not have TC or abs, also forgot on the original post but the car is at about 102,000 miles, the odometer is out so I dont have true mileage

I ended up checking the tubing for the EGR, both the valve and the vacuum solenoid, the tubing is good. Same for the voltage and resistance. The solenoid though when blown into with a tube is letting air through the other side. Unsure if that would cause the problem or not

EGR vacuum

 

The EGR vacuum solenoid is good, actuated when power was put to it

 

Can you keep it running by using two feet? Keep it above idle with a little throttle. It may have lost a vacuum cap or a couple vacuum lines and be really lean at idle. Or the temp sensor may have failed and it is extremely rich. Do you know the difference?

 

Code 81 seems to be a comm error between the PCM and ABS module. Per my 95 FSM. 95 had ABS, so the definition of that code must be slightly different.

Code 19 is a 6X signal fault.
This output signal is a square wave that momentarily drop slow at each of the six 60° ckp pulses.
There is also a reference signal which I believe is generated by the ignition control module. This feeds into the PCM.

Code 19 sets if

1. There are not three 6x pulses between reference pulses, or
2. A 6X pulse does not immediately follow a reference pulse

That being said, seems like an issue between the electronic ignition AKA ICM module and the PCM. Either a wiring issue, loose or corroded connections, shorts to ground, possibly the PCM, possibly the ICM.

It seems the 6X pulses are keyed to the ckp pulses, so I'm also wondering if it could be a ckp issue where 6X pulses are missing because ckp pulses are missing. No ckp signal kills spark and fuel injectors and would most definitely stall the vehicle. It's not uncommon for these sensors to intermittently fail as they are on their way out. I don't know that I've ever seen a code 19, hence my roundabout explanation and interpretation.

See the code 19 troubleshooting tree below.




Code 26 is the illustrious quad driver fault. Two circuits monitor 8 devices, 4 each. If a fault is detected, the PCM is informed via the quad driver interface and the SES light is illuminated.

You only mentioned a few of the devices that are monitored by the quad drivers. I'm wondering where you are sourcing your information regarding the possible culprits that can trigger a code 26. I am not implying your information is incorrect. I'm trying to determine if everything being monitored in 95 is the same as what was being monitored in 93. I can't see it being terribly different.

I'll come back and post the code 26 diag tree tomorrow morning.

Code 81 is a communications error between the ABS controller and the PCM. At least in 1995 it was. Makes me wonder if the explanation for this code is different in 93 versus 95. That will take me a bit of time to figure out in all likelihood.

I would check the resistance of the ckp while installed. Also check the connector for corrosion. Check the ckp wiring back to the PCM or do a continuity check and wiggle the wires to see if there is an intermittent connection issue.

SPECULATION
My gut feeling is that the ckp is failing and the coil inside is damaged and vulnerable to both expansion with temperature and vibrations. I'm guessing that when the mechanic started the car up and let it idle for 30 minutes, it kept running because there were no road vibrations to momentarily interrupt the ckp signal. Turning it off and turning it right back on and letting it run again sitting in place works for the same reason I just explained.

The intermittent nature of code 19 showing up is consistent with how these ckps often fail.

Code 26 should always be diagnosed after all other codes are addressed due to the number of different circuits being monitored by the quad drivers. Everything from evap solenoids to EGR to I don't quite remember because it's late and I'm tired, but you get my point. I'll look at it again tomorrow, but the point is code 26 can set or clear based on other codes setting.

 

If enough EGR gets through at idle it can stall the engine.

 

You did state probs began after you filled up with gas.
Bad gas?

Did the car sit for an extended length of time?
(Fuel filter?)

Have you checked the vac line on the fuel pressure regulator under the hood?

Does the vehicle stall when you take your foot of the gas to slow down, when you hit the brakes to slow down, or as the vehicle approaches 0 mph and the rpm drops near idle?

What RPM does it idle at when it is not acting up?

 

The part you have pictured at the top is not an EGR.