Just joined the board but I've been viewing off and on for a while. Recently purchased an 88 GTA. 5.7l tuned port injection. The car will NOT start cold. Just cranks and cranks. The guy I bought it from said it just started running like crap one day. He replaced plugs, wires, cap and rotor. Replaced ignition coil, throttle position sensor. after that didn't work he got fed up and sold it to me. Checked spark and all is well in that department. Fuel is dicey, Measured fuel pressure @ valve on fuel rail. No pressure reading when ignition is turned on. You can watch the fuel pressure build as you crank and it won't fire until at least 25 psi is built up, runs like crap for a second and shuts down.Then won't fire. I found that after you've tried to start it for a while with no luck and you let it sit for about 10 minutes it fires immediately, runs like crap and dies. I've checked all connectors, wires and hoses. All vacuum hoses are new. Nothing really obvious jumps out at me. If anyone has run into this before or has a direction for me to go in for repairs it would be awesome. Wanna make my 700 bucks I spent on this thing worth it. BTW, I had the fuel pump, fuel filter and fuel pressure regulator replaced last week. Still no go.PLEASE HELP!

 

I'd have said fuel pump if you didn't just have it replaced - but 25 psi sounds like much too low for a tpi car so there is some issue there still. When you turn on the ignition the pump should prime the rails and you should have pressure. After that when the engine turns over the distributor can trigger the fuel pump to run which is what you're seeing. I'd double check (replace) the fuel pump relays for peace of mind, and never assume that all the work was done correctly. Good luck.

 

Fuel pressure should be over 40 PSI when priming. The computer will prime the pump for 2 seconds when you turn on the ignition. Once the oil pump produces 2 PSI of pressure, a switch takes over and keeps the fuel pump running.

 

When I got my car the previous owners had put a new fuel pump in it. Somehow they got a V8 TBI pump in a V6 box. I got the pump box when I got the car. I would suspect either a bad relay or wrong fuel pump or both.