Mechanics

WE TOOK OUR CAR IN FOR "HARD START, LONG CRANK". OUR MECHANIC RULED OUT FUEL PUMP AS IT WAS GETTING ENOUGH PRESSURE...SO HE REPLACED THE ELECTRONIC CONTROL MODULE FOR $290.00. ECM PROGRAMMING COST ANOTHER $109 AND "DIAGNOSE AND INSTALL ECM" ANOTHER $224

1997 Cadillac SLS • 160,000 miles

It just doesn't seem like the problems are related to us. Why replace the ECM for a hard start, long crank right off the bat? Please be as specific with your answer as possible. Thank you.
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Garythegreat
December 30, 2011.



Did car get fixed by new ECM? Did you ok it's installation? Was any exact reason givin for it's replacement?

Tiny
Fixitmr
Dec 30, 2011.
Did not fix problem, idle air control motor not responding to ECM, ok'd install of ECM, put in new IAC motor, still idles at 2600rpms, ask me to return old IAC to reinstall. Do not understand his reasoning, his explanation was too confusing. Something about not being compatible. He still has car!

Tiny
Garythegreat
Dec 30, 2011.
Did it just start doing that when it got cold or has it been like that

Tiny
Kristencupp
Dec 30, 2011.
No cold. We live in Arizona. It happened a few times within the past month, mostly when we've gotten in it in the morning to go to work. But once after we had driven it about 10 miles and had stopped for lunch. Is the ECM and IAC related in any way. We do not understand why the mechanic went straight to the electonic computer module (or whatever) for this problem.

Tiny
Garythegreat
Dec 30, 2011.
Here it didn't show but in my email it said 'no communication with IAC'? I see alot of ECM replacers when anything hints to ecm connection. I would first think you have a vacuum leak like backfire valve which is common problem. But if DTC's indicated anything pointing to possible ECM that's usually enough license to sell/install 1.

Tiny
Fixitmr
Dec 30, 2011.
At least the mechanic should keep your old 1 as a TESTBED for future work? Or sell it to someone else who wants to try ECM replacement thru local ads like craigslist?

Tiny
Fixitmr
Dec 30, 2011.
The mechanic put the old IAC back on car and told us it was now working. When I picked the car up and drove it for about a mile and a half, I could tell that it was racing. It pulled on its own without accelerator. I parked it in our carport and when I put it in Park, it raced to 3000 rpms. I'm taking car back to mechanic to fix this problem. What is the problem with it racing?

Tiny
Garythegreat
Dec 30, 2011.
Take it to get the codes checked at the parts store. If the idle speed control sensor is shot. You will have that code set for a isc sensor fault.

Cadieman
Dec 30, 2011.