weird don't have a clue

[mcrollin5]

hi everybody i picked up a 91 camaro 3.1 i dont have any back ground except the car would not run and then set for a few years.people i got car from swapt some ecm's and got it two run but runs like poo.so they said maybe ecm prob sence they did not have orig ecm. so i picked one up at a salvage yard for 91 camaro 3.1 but car runs for 1/2 sec then dies and will not restart.now if i put the ecm i got with car it runs but no power takes miles to get up to 35 mph (bringing car home) idol seems ok revs fair but when you put in gear just no power. so i saw that the map was umpluged so i pluged it in car died right away would not start untill i unpluged it would not run with salage ecm either i also got a new map same thing.i have changed fuel pump no diff.checked timing sames ok.so if ya have any ideas it would be a big help cause im left scratching my head thanks

[97copcar]

You may need to have the ECM programmed for your car. I now that there are differences in the ECM's. I have a 97 Z and a buddy works the parts counter. I picked up a ECM for my car and gave him the part number. I was lucky in that it was compatible. It was recommended to me that I have the program flashed to my cars specs since it is a B4C.

You might want to check into the price of a ECM flash and update.

[abaird]

Catylitic converter could be plugged. I would check fuel pressure just to be sure it is ok. With the engine idling, spray carb cleaner around the intake manifold to see if the engine speed changes to check for large vacuum leaks. Just a few easy things to check first.

[93gmcjimmy]

Yeah I'm gonna go with fuel problem is likely as well. Check the fuel pressure, I believe there is a schrader valve on the back of the engine to check it. Also go buy a new ecm at the auto store and not Auto Zone. Their crap is as bad as getting it out of the junkyard. ECM's are common to go out and can cause untold kinds of probs. Also check your spark. Check the coil to make sure it's puttin out 30 or 40 thaousand volts. You can do this by touching your tongue to no. 1 wire and crank the engine over. If your socks are still on then you need to replace it An auto store should be able to check it for you.

[Prix87]

Are you getting any trouble codes? Whats your Check Engine Light doing when you turn just the ignition on and then crank the motor over? . Your timing could be off aswell. What was it set at BTDC? Bum timing could explain sluggishness and if your having any backfires. I had a shot ecm in my 85 2.8 mpfi and it ran in "limp mode" which was extremely sluggish, no power but would idle somewhat smoothley. Check engine light was on, stayed on while running but would not flash any codes when grounded... Given that it ran with one ecm n not the other i'd point my finger at that. Also agreeing that these ecm's go hay wire and create weird problems!