Can an ECM be bad and not know it?
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Joined: Oct 2001
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From: reidsville,nc,usa
Car: 1989 Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 9 Bolt Borg Warner 3.27 gears
Can an ECM be bad and not know it?
My car has been running like ****! I've got a new cap,rotor button, cleaned and re-gap the plugs, wires look good, checked timing, new fuel pump and FPR. Disconnected the battery to reset the ECM and drove it to reset the IAC. According to my scanner, the TPS is at .45v and it showing a rich condition. All the info looks like its in spec. The only thing I can think of is a bad ECM. The O2 sensor varies alot while driving. It can be at 700mv and drop to 40 and then back up again all over the place. It does change voltage rather rapidly which I think is normal. I have looked for vac leaks and can't find a thing. Maybe a bad eeec? This is driving me crazy!! Idle is bad with a 'skipping' and sputtering exhaust. Bad cat? HELP!
Ken
Ken
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Can an ECM be bad and not know it?
Check the resistance of the injectors while they are hot. Any that are under 12 ohms are bad.
If they are the original Multec injectors just save yourself the trouble and put some nice Bosch ones in. See LinderTech and/or Southbay for replacements.
Note that to set the IAC and the ECM idle control, need to do an idle learn. Search with my name as the author along with 'idle' and 'learn' as key words.
RBob.
If they are the original Multec injectors just save yourself the trouble and put some nice Bosch ones in. See LinderTech and/or Southbay for replacements.
Note that to set the IAC and the ECM idle control, need to do an idle learn. Search with my name as the author along with 'idle' and 'learn' as key words.
RBob.
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