[Help PCM no ground injectors-LT1]

#1. Flooring the gas or holding the throttle plate all the way open on a fuel injected engine will turn off the injectors.What is your TPS voltage when the throttle is fully closed, engine off. It should be at about .5 and no less than .23V or it will set a code. When I installed the my 58MM Holley TB I had to round out the holes on my TPS sensor to get it back down to .3V so that it would stop setting the Code 21(TPS too High).Heres what I suggest. Go to www.alldatadiy.com and buy a subscription for a 1995 Camaro with the 5.7. Its way better than a Haynes and it gives trouble shooting info and lots of pictures. Its $25/year for your first car and $15/year for any car after that or for resubscriptions. IMHO its money well spent. I would have spent way more time screwing around on forums asking questions and not getting the info that I need to get my LT1 running like it should if I hadnt have bought that subscription. Trust me on this one! I could give you the info for a 93' LT1 but the injection system isnt wired the same because the 93' is bank fired and not sequentail fired like yours is.Guy

M

Check the basics:

Plug wires routed correctly and not arcing or in bad condition (LT1s are very sensitive to spark breakdown)

Make sure you have fuel pressure (invest in a pressure gauge that screws into the shraeder valve on the rail)

If the opti is going out, you will usually have a slight miss at idle and a hesitation under load...it should at least fire unless its completely bad)

Check for vacuum leaks. Make sure that all unused ports are plugged, esp. at the throttle body. Try unplugging the MAF, and let the PCM default to speed density. That way if you do have a leak somewhere the PCM can account for the extra air.

 

Tim

My name is jamal and I have a 93 firebird formula with a 97 engine wire harness and computer. My question is that my car won't fire and the injectors are not getting ground but getting power can you help?