Well I finished changing my cam, lifters, pushrods, rockers, adding guideplates, and heavy duty 1.44 crane springs.. I also added an Aeromotive AFPR........

Get the car back together, turn the key on and off a bajillion times for the fuel pump to prime the rails........ and...... Nothing! It'll give a cough every 5-10 seconds of cranking... So I check spark... Wicked strong, Check the computer by reading off a file, and reprogramming it with LT1 edit with the same file.. looked good... Check the fuel pressure at the fuel feed to the nitrous, Huge spray... So dad takes off the line (the one I put on the schrader valve for the nitrous), puts it in a squirt bottle, I fill it up half way with just two primes he sprays it in the motor a bunch, I crank it up floored.... and we go deaf........ for a second... it screams to life and dies just as fast... we did this repeatedly (just no floored!) So its not getting fuel......... cant figure out why though! any help would be greatly appreciated.

 

ok everyone, jam the easter ham down in your bellys and help me!!! lol kidding

 

either your fuel pump isn't working (but it most likely is because it's priming) or the injectors aren't injecting. Sounds like a problem. I assume all teh wires are in the right places? Have you tried starting fluid?

 

well the pump is working, and It will run for a sec or two on gas, dont like using ether because it can damage rings. Im assuming the injectors are not firing any reasons for them not too?

 

oooooooooohhhh oooooooh revelation! new idea, in my head, cant try today cause the car is at my dads shop and he aint going today.... Could it be the Adjustable fuel pressure regulator is set WAAAY high right now ( i dunno what its set at yet)... and the pressure is too high for the injectors to open? is that something possible? other than that ill check my injector relay, and put a noid light on the injector, after that im outta guesses.

 

Yes thats a possiblitly, but thats what I was going to say, could be your Fuel Pressure Regulator.

my $0.02

 

Holy what the funkin heck? It RUNS! all I did was back the pressure regulator down from its start point.....something stupid simple... always takes the longest to fix!

 

Ok well the other day I posted I couldnt get it to start after swapping to a comp cams 236/242 and all the supporting valve train mods... I plugged in the brake booster line I noticed was unpluged, and lowered the fuel pressure and it ran...
Today I tried tuning it, no matter what I do, when I hit the gas, all it does is rappidly backfire out the headers, and die. and I have to really play with the pedal to keep it alive... I adjusted the valves again today, and they looked good, Its something with my fuel system or PCM, but im getting really pissed with this damned GM fuel injection setup.

 

can anyone please help?

 

Steve are you throwing any codes?

 

not that I know of but it stopped runnin today, again, when I try to start it back fires out the exhaust, and then out the intake! like the timing was WAY retarded, and way advanced all at the same time, Im swapping the opti to a new one I got at Autozone, a remanufactured one.

 

... you got ALL the vacume lines hooked up????? Friends car would NOT stay on for more than a sec.... because some of the lines were disconnected....

 

all hooked up or plugged up :-)

 

Ok I had an excellent running 11 second NA hotcammed race car, I swap to this Comp Cams cam 236/242, and now it WONT run , I jacked with the fuel pressure a bit and the car came back to life, ran decent too, then it ran poorly, and now it doesnt run again, I changed the opti and it still does the same thing, I crank it and it coughs out the intake and exhaust.. Im totally stuck if I get it to run, its only for a few seconds.

 

Ok, so far Ive got,
200PSI Cylinder pressure on the compression guage, (cam installed correctly)
43.5 psi pressure at the schrader valve,
I cleaned off a plug, cranked it for 20 seconds, and checked the plug, there was fuel on it, I replaced the Opti, and the Coil, and the car still dont run, im running out of options here. I think its the ignition

 

well do you have spark? have you tested that yet? how old is your ICM? that's under the coil.. see if you have spark..

 

I Had spark, dont think I do any more since the plug is wet, I was just thinking Ignition Coil Module, or control module or whatever, im going to buy one now, last thing I can replace, the old one is stock

 

Check all your grounds as well.. especially the one's below the coil

 

never mind, I finally got someone to crank it over for me while I checked for spark, its got a decent spark on it... I dont understand wtf is wrong.

 

ok, so Ive rigged up my nitrous system to supply fuel only, I primed the rails, gave it a couple WOTs to spray fuel in the intake, and crank crank crank crank.....15 seconds, not even a pop, nothing, I turn off the nitrous system, hold it too the floor, and cranked, nothing... now Im sure its getting fuel & its getting spark, and its got 200psi compression, Wtf is going on.