1990 Oldsmobile Cutlass Will not start

1990 OLDSMOBILE CUTLASS
11,000 MILES • 6 CYL • FWD • AUTOMATIC
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MICHAEL FITZWATER
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Replaced fuel pump. Has spark. Tries to start but will not continue to run, sometimes it backfires through the air nozzel. It has been getting harder to start each day after pump replaced. No air in fuel system, has good pressure. Seems to out of time.
Feb 28, 2010 at 3:37 PM
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RASMATAZ
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Hi Michael Fitzwater, Welcome to 2carpros and TY for the donation

Inspect and test the coolant temperature, throttle position and manifold absolute pressure sensors-also clean out the idle air control valve and EGR valve to include the testing of the fuel pump relay and fuel pump/oil pressure sending unit
Feb 28, 2010 at 7:01 PM
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MICHAEL FITZWATER
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Your reply assumes I am a mechanic. What does the coolant temperature have to do with the car not starting?
How do I test the throttle/manifold absolute pressure sensors. also how do I clean out air control valve and where is it?
Yesterday when I pressed the scharder valve to test pressure just a very small amount came out and not much pressure.
Michael
Mar 1, 2010 at 9:42 AM
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SCOTTY DEE
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What's up Fitz? Engine coolant temp tells the computer how much fuel and air to send. On startup, the engine needs all the fuel and air it can get. When the engine coolant temperature sensor realizes that the engine is warming up (i.e. the temperature of the coolant flowing across the sensor) the computer retards air and fuel mixture.

These models of Oldsmobiles as well as other GM cars with the same platforms had high failure rates of the ECM (engine control module) or engine computer. It would help to see if the OBD1 (first generation) will allow you to communicate with it.

How long can you keep it running before it dies?
Mar 1, 2010 at 3:53 PM
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MICHAEL FITZWATER
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Scotty,

OBD1 was checked before the pump was replaced, no codes.
This AM I sprayed STARTER FLUID into the throttle bady and it would run as long as I sprayed but not beyond that. I had the car towed to my local dealer as I need a car NOW. They are the ones that replaced the pump.
Mar 1, 2010 at 4:12 PM
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SCOTTY DEE
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I hope they'll test the PCM. Just because it's at the dealer dosen't mean they have the best techs. Believe it or not, one of the best ways to test one of those was to slap it, (ECM) and see if the car died.
Mar 1, 2010 at 4:23 PM
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MICHAEL FITZWATER
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I dislike the Dealer route but need the car...
You said to check the PCM. Do you mean ECM or is two different things
Michael
mafitzwater@yahoo.com
Mar 1, 2010 at 4:27 PM
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SCOTTY DEE
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Alphabet soup is what it is. ECM, PCM, they are the same in the regard they are both engine contollers. But, there as many as 12 different CMs (Control Module) on most cars built after 2001, that monitor just about everything else on the vehicle. Lots of fun sometimes!
Mar 1, 2010 at 4:33 PM
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