i have a 92 305 tbi camaro RS with everything stock. First off it takes about 6 secs to crank the car, and then once started the car's RPMs jump from 1500 to 500 to 600 and most of the time it dies. While the car is doing this bouncing in RPMs i can give it gas and sometimes it can keep it alive and sometimes it kills it and other times it doesn't even respond to gas pedal movement. Every once and a while, like maybe once per driving session, i hear a backfire from around the passenger side, right about where the catalitic converter. Sometimes i get a code 44, which is lean exhaust. I did some dianostics on it:

O2 Sensor voltage went from:
Idle @ 220º - .74v to 0.0v
2000 RPMs @ 220º - 0.1 - 0.0v

Open and Closed Loop:
Idle @ 180º - closed loop(SES light blinking 2.5/sec) and sometimes the light stopped and sat there.
2000 RPMs @ 220 - open loop to closed loop to open loop to no light

Okay now for the things i have replaced or done.
Replaced ECM
Replaced MAP sensor
Replaced Oxygen Sensor Twice
Replaced IAC
Replaced Dist. Cap and Rotor Button
Replaced Plugs and Plug Wires
Replaced fuel filter
Cleaned throttle body and fuel injectors and replaced gaskets

P.S. Please note that i have thought about the fuel pump, but the car doesn't always do it. Every few cranks the car runs like new again. Please Help!!!

Thanks,
Brice

 

0 volts from the o2 isn't right, filters all good, compressions ok, cat not clogged, egr working? that would be a a few of the places i'd looks first as well as checking fuel presure. with ecm controled engines one problem will make other problems and you still need to remember the basics, like a good tune up.

 

Wow! That's a lot of replacing. For the cost of the ECM alone you could have had a nice fuel pressure gauge and adapter for your TBI. Now you'll have to try to get one anyway to check the fuel pressure.

 

What ended up being the problem??? Sounds almost exactly what problem I am having right now.