I have a 2003 Saturn Vue 6CY FWD with 70K miles. During the last month, we have been having intermittent stalling problems.


The problem normally only happens after the car has been driven for 30 minutes or more is shut off for 20 to 30 minutes and then driven again. The car starts sputtering and looses power (will not respond to accelerator) then it dies. It died once at a stoplight and another time on an over pass on the freeway. The engine will restart with a few seconds of extra cranking and run rough. If I shut the engine off and let it cool for an hour, it starts and runs without problems for as long as a week.


After the second stalling incident, we took it to the shop and they replaced the fuel filter and did and serviced the injection system but were not able to reproduce the problem.


After the second incident, they tested the fuel pump and found the pressure to be within the normal range. They replaced the crank position sensor because it they said that it could cause the symptom and it is relatively inexpensive. They found a catalytic converter efficiency fault code.


The dealer replaced the catalytic converter under warranty and I drove the car a couple of days without any problems. After these changes, the car seems to have a little less toque and acceleration was smoother than when the car was new.


About 3 days later the car stalled again and after restarting it twice I drove 4 blocks home without problems, but the check engine light came on. The next day I drove 10 miles to the shop without any problems. The shop said that there were two codes P0341 cam position out of range and another cam position sensor code P0335. When the technician touched the sensor, the computer quit sending errors and both codes disappeared. The technicians drove it for a week as their own car and were not able to reproduce the problem.


I'm thinking about replacing the cam position sensor and doing a fuel pump current draw and waveform test. I am an electronics engineer so I have the equipment to do this test myself. Fuel pumps are too expensive to replace as for shotgun diagnostics.


It is difficult to fix a problem when you can't get it to occur when you want it to. The mechanics are frustrated and my wife wants to get rid of the car. Does anyone have any ideas about what I should do next? I've thought about trading the car the wife, but that probably is not a good option. Help!


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What you have here is a failure to communicate (guess what movie?) and the worst part is to capture thesignal loss at the moment of occurrence. A laptop/digital storage scope software would make an ideal sensor monitor for the cam position and crank position sensor. I would guess the same can be applied to the fuel pump but beware; the fuel pump will cycle on for 2-seconds then shut off if you leave the ignition key in the ON/RUN position. Its a safety issue so when the igntion key is turned to START the ECM/PCM will detect the crank position sensor signals and then allow the fuel pump to run, the ignition to spark and the injector pulses to fill the cylinders. The cps and cam positon sensor share duties. No cps = no fuel pump, no ignition, and no injector pulses. I believe the engine can run w/o the cam position sensor but in the 'limp home mode' where engine revs are restricted to below 2000 rpm. An outright failed cps won't allow engine running; you can crank the starter all day until either the battery dies or the starter burns out and the engine won't fire up. On the other hand if there's an intermittent cps failure that can be tricky to isolate; its become temperature sensitive with still no rhyme or reason. It can work only when the engine is cold or when warmed up. BTW, I believe we share the same 3.0L V6 engine, mine in the '03 L300. And I have the FSM's. The wealth of information I may be impressing you with is not mine but from another site, http://saturnfans.com. The failures of the cps has occurred on both L-series and S-series models with similar symptoms.


DTC P0335 CKP Sensor A Circuit Performance


DTC P0341 Camshaft Position (CMP) Sensor Performance


P0335 still suggests the crank position sensor as the problem, CKP is theGerman abbreviation for CPS. CKP/CPS


P0341 says it all but I haven't come across any failures of the cam position sensor unless you have a chaffed/loose wire somewhere?


The two may come up as the engine dies while running but again the posts from other owners have never had these two codes come up in diagnostics. Only the cps failing/failed and subsequent replacement was the guessing correct for almost every similar symptom such as yours. As to the fuel pump, I agree its an expensive item and rarely fails as its buried in the fuel tank. I would look closely at the fuel pump relay instead, substituting with the horn relay.


And in closing, here's the list of OBD II codes; http://www.saturnfans.com/forums/showthread.php?t=44822Edited by: ducky

 

Thanks for the reply. The manual says the engine is a 3.0L L81. I have been reading the information on the P0341 code on the S series. The threads indicate that the engine on the S series does not have a cam position sensor and that the code is generated by intermittent ignition component problems. Do you know if this engine has a cam position sensor? If so how can I locate it?


I probably need to buy a set of factory service manuals now that the extended warranty has ended. The extended warranty was a good investment. I have been happy with the car @ 70K miles, but I have had the following replaced under warranty:


All 4 wheel bearings @ 40K miles (I consider this to be a design flaw.)


Oil pressure sensor (located in a bad place where it gets a lot of exposure to water)


Catalytic converter (I've never had to replace the converter on cars with a lot more miles)


Crank position sensor - Replaced to troubleshoot stalling problem, but not known to be bad.


Squeaky steering column - lubricated the boot at base of steering column with silicone grease.


Dead battery - replaced twice. When batteries go bad, there is no advance warning on this car. It cranks fine one time and the next time it won't even click the solenoid. I usually get some advance warning with other cars.


P0335 CKP Sensor A Circuit Performance - Any idea what performance means? This is vague.

P0341 Camshaft Position (CMP) Sensor Performance - I've replaced the crank position sensor. This one is vague too!


I have a battery powered digital storage scope, but breaking out the signals and recording them for weeks to catch a one shot incident will be a real challenge.


Thanks
Edited by: prawlings1

 

Uh, you may have missed some of my replies, particularly the crank position sensor- its abbreviation for the forum is cps but the EFI system is Robert Bosch (GERMAN) and the factory/OBD II codes will list it as ckp instead of cps. P0335 CKP Sensor A Circuit performance means the crank position sensor, not the camshaft position sensor. The cps either works or is faulty as explained previously. P0341 Camshaft Position (CMP) is not the crankshaft position sensor. Please review these two sensors carefully as you may have only replaced the camshaft sensor when you may have a crank position sensor failing intermittently. CKP/CPS is the crank position sensor that you are describing as the most likely faulty component.


For the L-series carswe havean additionalcamshaft sensor mounted adjacent to the camshafts, near the front of theengine, left sidetowards the radiator, as indicated by the small gauge wiring harness'. The camshaft coverwill havethe sensor poking in and will be located next to one of the camshafts. The crank sensor will be below and protruding into the engine case next to the crankshaft, front cylinder bank, right or left of the oil filter assembly, mounted with one bolt.

 

Thanks for the response. I may have used the wrong acronym in the previous post. The problem occurred after the Crank Position Sensor was replaced. I realize that the new sensor could also be intermitten, but I'm considering changing the Cam Position Sensor because I got both a P0335 and a P0341 error. Here is what I know about the errors:
Code P0341 – Camshaft position sensor
Arcing on boots or coil
Bad spark plug connections
Camshaft position sensor circuit open or shorted
ICM damaged or failed
PCM has failed

Code P0335 – Crank position sensor
Wiring open (intermittent)
Wiring shorted (intermittent)
Bad CKP sensor
Interference on CKP wiring – too close to spark plug, generator or other EMI/RFI noise source

I have also had a fuel injection service done. The really bad thing about this probem is that it only happen a couple of times a month and it never acts up long enough to get much useful diagnostic information.


I'm longing for the good old days before all this smog control junk.