I have a 86 trans am automatic with the 5.0 TPI, hard to start and I check fuel pressure is at 10psi, car has new a/c delco fuel pump and new fuel filter. What else can it be?
thanks

 

This is for 1989 but yours should be similar

 

Kinda hard for it to be much else other than the fuel pump.

"New" and that nice $$$$ "AC Delco" writing on the box (who knows who actually made it) are no ""guarantee" that it's actually working right, unfortunately.

 

ok thank you!

 

do you know fuel pump relay location??

 

On the firewall - upper drivers side. Its the relay on the left in this picture. 86 might be slightly different.

 

If it is a TBI fuel pump, that might be about all you get. It wouldn't be the first time a part made it into the wrong box, or the order picker grabbed the wrong part.

It would also be good to restrict the return line to test the pump maximum pressure, just in case the FPR is faulty. Then make sure the pump is actually getting 12V back at the tank, not just at the relay. I'm guessing that the pump is new because the old one was not making pressure, opening the possibility that the pump was/is not the problem.

FWIW, the '86 relay layout looks more like this:

 

​​​​​​​Didn't think of that, but you're right. It could be a perfectly working one of those.

 

thanks gotta call sumit racing in the morning