I've been having this problem where on occasion my injectors won't fire. I have replaced everything on the fuel system except for the pump & the regulator. I tested the pressure coming from the pump and it is right on par at 13psi. However I didn't check the pressure on the other side of the throttle body. So I'm wondering if the pressure regulator on the TB could be my issue. I have replaced the ECM and installed a resistor bypass on the VATS so I didn't think that was it but I don't know. I was going to by the VATS bypass module by painless but Summit tells me it won't work for TBI. any ideas on this? Thanks in advance for any insight you guys and gals can give on this.

You might have a problem w/ the ignition system, like the ign. module or pick up coil. When you loose injector pulse, see if you loose spark as well. The ecm uses a reference from the distributor to fire the injectors.

i have a few questions and need help im buying as l98 from a friend and gonna rebuild it i have a lt1 cam would that cam work fine in that l98 would it give me more hp or tq from the stock cam thats in it and im keeping tbi right now i have a 305 tbi im gonna go 350 tbi would all do i need to change if not use the lt1 cam what cam should i use ? im gonna get a bigger tbi and bored out and everything done to it to and i got the chip issue fixed to what can i keep on my 305 to use on the 350 ?

Maybe...
But before I did the stuff on the fuel system I did pretty much everything on the ignition system first. New coil, wires, plugs, cap, rotor, distributor & module. I did check my spark and I'm not losing that so my guess is as good as any. I've done pretty much everything I can think of except the fuel pressure regulator so I guess we'll see.

ok so
1)how long has it been sitting
2) the Fuel pressure Reg. doesnt work before the gas reaches the injectors, it kicks in after then it starts refulation. what im currently doin to mine is going to open my housing up and clean the injectors and get into the fuel block and see how dirty it is in there.

Actually it does start and run, and I drive it most days unless it rains (t-top leak). Just occasionally it won't start and when it does this I'll have spark but no injector spray.

so does it backfire?

Nope. No backfire and timing is dead on. I've been hoping that replacing the ecm will fix the problem but won't know until it pulls this no start thing again if it does it again.

does your car give any error codes, engine light?

That's another weird thing. No codes either. As you can probably tell so far this is a very perplexing problem.

ok so, no backfire, no codes. and so does this happen: your driving and all of a sudden your light dim and car either powers off or seems to want to turn off? and once off it wont start?

As EX stated you may want to check the connections within the distributor.

When the car starts and runs it runs well. I can stomp on the gas and it doesn't struggle at all and has good throttle response I checked the connections in the distributor and tested the module and pickup and both were good. The last time this happened it was about 20 deg out but I wouldn't have thought that would cause it not to start but just to start slow.

ok so now i would check the alternators brushes

Hmmm...Now there's something I hadn't thought of. The alternator tested good when the battery was replaced but with the price I can get a new one for I may as well think about replacing it. After all there is about 157,000 miles on the car.

I did replace the dist but the replacement was a reman and for 50 more bucks(I think) I could have had an MSD or Accell distributor.

Thanks for all the suggestions guys