on my 94 z28 cranks afew times than fires up?? only happends on cold start ups, this just started to happend after i replaced my fuel pump and fuel pump relay.thanks

 

Whats your Fuel pressure at KOEO?

How old is your starter?

How old is your alternator and have you had a local shop (advanced auto, Autozone) hook it up and make sure its charging the system?

 

What brand pump??? Delphi, Bosch, etc??? I have seen new pumps that do not produce the correct pressure...

Hows the fuel filter??

 

1freak, plz state what you problem is in the topic line
Hal

 

fuel pump is an delphi hi pressure/ i have not tested the fuel pressure yet i will though/ starter and alternator are working fine about 1 or 2 old. is the stock fuel pressure reglator adjustable??

 

The stock fuel pressure regulator is not adjustable, and it doesn't need to be.

You should prime the pump, without starting the engine. Should be over 40psi. Then watch how fast the fuel pressure drops. If it drops quickly, its going to take longer for the engine to start.

 

ok i will do that ill let u know the results, so is that normal for a new fuel pump?

 

Any fuel pump, new or old, has to hold the pressure in order for the engine to start quickly.

 

so lets say i tested the fuel pressure and drops quickly their for my engine will start slow,what would u recommend drop the tank again and this time use a dealer part?. the delphi i bought is an oem upgrade hi pressure fuel pump

 

There are other things that can cause a rapid pressure loss, including leaking fuel injectors and a faulty fuel pressure regulator. I wouldn't consider going into the tank until I had ruled out those two possibilities. Its pointless to spectulate until you check the fuel pressure.