mguidry629

iTrader: (6)

96 Z28, rebuilt stock motor, stock everything, just installed Saturday and won't fire up. I tried 95 and 96 pcm. I'm getting spark, I'm getting fuel pressure, but I'm not getting fuel. Car will fire up on starting fluid, so either my injectors are bad or the pcm is not firing the injectors.

What can cause injectors not to pulse? How can I test to see if I'm getting a pulse? I'm getting 12v to the injector with key on. Maybe injectors are bad? I've accumulated 4 or 5 intakes with injectors/fuel rail for LT1s, and I just grabbed the fuel rail/injectors off the intake that looked "the best". I guess I will just swap out the fuel rail with another on the shelf, but I was hoping for a way to figure out if it's the injectors or something else.

warriorcustoms

iTrader: (10)

Triple check everything I did a clutch in my S10 once & pinched a wire Which in turn caused a no start condition

killerz97

iTrader: (1)

Check the injectors with a noid light. Its very unlikely that all the injectors are bad. If you have tried starting it a bunch you might have flooded it. Hold the gas pedal to the floor and try starting it.

mguidry629

iTrader: (6)

I guess I'll have to get a noid light and start there. I searched and found a post where someone was having the same problem and it ended up being that all 8 injectors were bad. I'm kinda hoping that's the problem since I have plenty of stock injectors and I don't want to be chasing down a wiring problem. Thanks for the input, hopefully I can work on it today and get it figured out.

quik95lt1

iTrader: (7)

check fuel injector supply voltage fuses in block.....two 7.5A's.....should have 12V at red wire on injector at all times when key is on

SS RRR

iTrader: (2)

Isn't there something in regards to if the PCM is not receiving a signal from the opti it will not actuate the injectors?

shix

could there be an issue with VATS also here? I had a similar problem when i swapped my 94 engine and pcm into a 96 car and I had to have VATS tuned out. Fuel pump primed and the engine cranked but it wouldn't actually fire and run until i had it tuned out. If you haven't done it, try it.

quik95lt1

iTrader: (7)

but he said he has spark.......think about it lol

possible but if he still has fuel pressure while cranking its not it......usually with a vats problem it will fire for a split second then shut right off....

mguidry629

iTrader: (6)

I checked the fuses and they're good, but I only remember seeing one fuse for the injectors, not two. Are they both in the block under the hood? I only tested voltage to injector #1 and it had 12 volts with key on. I can disable VATS on the 95 PCM and see what happens, but first I think I will test for a pulse to see if the PCM is even demanding the injectors to fire. If not, then I'll try to disable VATS.

I'll post what I figure out if I can get over there and work on it tonight.

SS RRR

iTrader: (2)

I know, but didn't remember PCM controls spark to the coil. I just remember the part about the PCM controlling pulses to injectors if there was no signal from o-spark and I scatter brainededly thought the opti/coil fired on its own, which is why it was in question form.
I learnt something today...

mguidry629

iTrader: (6)

Well, PCM was pulsing the injectors, so I swapped out the fuel rail and injectors for another set I had on the shelf and she cranked right up. Apparently if u let injectors sit up for long enough they'll freeze up.

Hooked up all the water lines and filled up the radiator and it's leaking so now it's on to the next problem but just glad to hear the motor run.

Putting a for sale sign on it as soon as I get it complete.

Thanks for the help as always!