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Bob, Auto Service Technician
Category: Car
Satisfied Customers: 4087
Experience:  40 year GM Tech. +30 Certified. ASE Master Tech.(expired, retired) Medium Duty, Heavy Line, Retired
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2000 saturn ls2: highway..sit..cranked..drove..engine speed sensor

Customer Question

i have a 2000 saturn ls2 that the engine just died going down the highway..sit for 10-15 mins. cranked and died morning jump started it from the flashers being on ,& drove it around for a 5 mins,no problem.pulled some codes off the computer,po171,po174,po727 & p1780 ,the 171 & 174 have been there 6 mos.the other 2 some time in the last month...could the engine speed sensor make the car die or should i look somewhere else..ty
Submitted: 7 years ago.
Category: Car
Expert:  Bob replied 7 years ago.
Could I maybe get you to have the system scanned again? The first two codes relate to the fuel injection system, but the last 2 are non existent in the Saturn service manual. Thanks
Customer: replied 7 years ago.
Reply to Bob's Post: i have scanned ,cleared & rescanned multiple times. the car doesnt run long enough to set the 171 or 174 codes & possibly the 1780 code(MIL),the p0727 code(engine speed ,no signal) pops back up every time it dies.I replaced the fuel filter ,which was clogged,but it still dies as soon as it gets warmed can i check out the coils without pulling the car apart,(for resistance maybe)also had code po335(CKP sensor circuit) pop up can i check these sensors out,ie;what voltage or resistance to look for....thank u
Expert:  Bob replied 7 years ago.
Man, I don't know if it is your scanner or my copy of the Saturn service manual, but most of these codes don't even show up on the list of codes provided in the book. I spent almost an hour last night after reading your question looking through the service manual and have to say that it really stinks. I can't find any resistance specs listed anyplace in it for testing sensors or coils, etc. Best I can do is opt out and hope someone else has some info for you. Most of the tests they do list, require a class 2 scanner, not a code reader, but a scanner like the dealers use. That's pretty much how they determine what sensors are within specs and what ones are not. When I get back from church, I will send a couple of pm's to some of the other guys here and see if they have any specs so you can use and ohm meter on some of this stuff. Sorry, thanks for your patience.
Customer: replied 7 years ago.
Reply to Bob's Post: thank u bob. what would u look at as far as the car dieing when it gets warmed up...thanks again terry
Expert:  Bob replied 7 years ago.
I think my first concern would be fuel pressure. You can rent a test gage from most parts stores. In fact Auto Zone has or had a free loan a tool program. Just show I.D. and leave a deposit and the tool is free to use. It should maintain about 48 psi running. Specs at key up are 40 to 55 psi and it should not loose any more than 8 psi if left setting with key on for 5 minutes. If it does, it could be a fuel module problem or a fuel pressure regulator problem. Let me know. Also considering the codes you had that I could check, you may well have an injector problem, but that is a pretty specialized test procedure. Thanks

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