I have rebuilt my engine in my 87 trans am GTA tpi 350. I have changed the following things, Dart Iron eagle II heads, Forged pistions, Comp cams roller cam, and the LT1 intake. The problem i am having is the computer IS NOT signaling the injectors to open up and let fuel in. I know because I have a injector noid light. It sounds like it is poping like it is trying to start but doesn't. I have checked spark, GOOD, i have checked and rechecked and rechecked again that the firing order 1-8-4-3-6-5-7-2 is correct and it is, I have rotated the distributor 180 degrees both ways and no fire, I have also added my own custom 89 chip with out vats (that is the custom part no vats) and still no fire. The ses light is coming on and the fuel pump is running upon start up ( I even checked it without the oil pressure switch hooked up and the fuel pump still runs while cranking). I have checked the computer (plugged it into my 89 Iroc and the Iroc ran fine so the computer is good), I have also eliminated the cold start injector( thats why I used a 89 version chip). I have about 47 psi of fuel. Summer is basically here and I am despretly trying to get this car on the road. I am getting VERY upset at this car and I am about to give up. Is there ANYTHING else that I might be doing wrong or something else that I need to do to eliminate the cold start injector?? PLEASE HELP!!!!!

 

I see that you are a tech so I'll assume you have a working knowledge of the electronics. Go back and check all the basics. Make sure you have B+ voltage to the injectors with key on and while cranking, and that it doesn't drop below 9V when cranking. If thats ok, hook a test light(a good one-i.e. snap-on) to B+ and test the ground signal from the ECM(this should be ok as it ran the other car) If it's not, test the trigger signal from the ignition to the ECM. Next I would check fuel volume, especially with the modifications to the heads and cam. I'm assuming you're still using the MAF which should be ok. If you converted to speed density(MAP) the cam is too big-not enough idle vacuum. Make sure the TPS isn't sending a WOT signal, resulting in fuel cut-back. Start at the beginning and check everything very carefully. After major engine work it's easy to miss poor connections, grounds, etc. Assuming the car ran before, it should run now if everything is in place. I hope this helps. Good luck, Pete.

 

Well I got it running!!! I replaced the ign module and that had no effect. I then checked my noid light and the bulb was not working!! So I put a 194 bulb in the injector connector and it flashed. So I then took a look at the injectors, found no signs of problems there, But I had 8 more 24 lbs injectors still on the tpi setup that ran the car last year. i switch them for sh_ts and giggles and tried once more and it fired right up. I am guessing that all injectors were plugged?? the ohms of them were arount 12-14.

 

The questionable injectors are probably still good. If they have
been setting for a long time the old gas in them has turned to
goo and plugged them up.

Submerge them in a can with injector cleaner and let them sit for
a few days. Then make a connector and flash them to a battery
to activate them a bunch of times. Don't hold the wires on the
battery just tap the battery to make the injector click. Some will
free up right away then put the rest back in the can for a few
more days.

That should free them back up.