91 buick ave possessed - ECM??

Hi there,
I'm desperate for some advice! I started the car the other morning, and it stalled almost immediately. Started it again, and it seemed fine. On my way to work the speedometer & dials died, then came back on as well as the engine light and battery light. The power steering failed, then the car died and although it would still turn over, it wouldn't start. When you put the key in you would hear all the relays clicking, the engine lights go on and off, fans turn on and off - the car went crazy! :disappoin
So we replaced the ECM, and now the relays have stopped, and the lights don't blink like crazy, but the car still just turns over but wont start unless you press the gas and hold it. The "service engine soon" light is still on. Was the ECM replacement not right? Any ideas on where to go from here? Thanks sooooo much in advance!
~Erin

What is the code?

I don't know how to pull the fault codes. I read some instructions that only said "Ground terminals A & B. Without turning car on, turn key to 'on'. 'Service engine soon' light will flash three times and then display trouble codes"...but i need more of a step by step instruction - ground terminals A & B? huh? Do you know how to do it?
Thanks!!

http://www.geocities.com/dann8785/serviceenginesoon.html
service engine soon

http://autorepair.about.com/cs/generalinfo/l/bl_dtcs_main.htm#1985
Diagnostic Trouble Codes

Thanks for the links! Unfortunately, I ran the test and the only thing that flashes is "12" (diagnostic mode). The car will still not stay running unless you hold down on the gas a little. While you're doing this, the "service engine soon" light does turn off, but if you just turn the key to "on" without starting the car, the light still comes on and stays on. Someone said we may need to reset the computer since we replaced it, by keeping the car running for a while, but in order to keep it running you have to press the gas, and i wasn't sure how long that would take, or if it was OK to do that.... Anyone have any more ideas?

Yes, the computer needs to relearn the operating parameters and it can take several trips down the road to do so. You need to take it for a drive like you normally drive and include a few wide open throttle pulls also. I am not saying that is your problem, however unless you drive it, you will not set codes for further diagnostics.

Success! We drove the car a little and now the code comes up - 21 (Throttle Position Sensor). It says to check the TPS for misalignment or sticking. Any advice on how to check if it is either of those two things, or should I just go ahead and replace it? If I'm looking at the right thing, it doesn't look like it can be very expensive...

The TPS has three wires. (1) black=ground (2) white=5.0 volts (3) blue=variable voltage (from .5 to 4.5). You need to test for voltage at different throttle openings. With ignition on, put one lead from your volt meter to the blue wire and the other to ground (engine), and operate the throttle through the entire range. You should have .45 to.5 volts at idle and you will have an upward progression with the throttle opening up to 4.3 volts + at WOT. If you test more than .5 volts at idle on the blue wire you may have a problem and you will have to bend the lever to get it below .5 V at closed throttle.