The car use to fire right up first thing in the morning.I have noticed in the last few months that it takes longer to start.It has enough juice,it just cranks for 4-5 seconds before it will fire up.It use to start as soon as I turned the key.The fuel pump and ignition coil are factory,so I'm wondering if the fuel pump is going bad.It mainly does it when sitting over night,the rest of the day it's usually ok.After it starts,there is no hesitation missing,etc., the car runs strong.Any other things I may want to check out first? My car is stock except for the CAI.Thanks

 

It might just need a tune up. Have you replaced the fuel filter (last 25K to 35K) lately? That is a cheap and easy maintenance item people forget.

 

Check the fuel pressure. Your symptoms are typical of the fuel pressure bleeding off too quickly after the pump primes and shuts down. If that's what is happening, could be a faulty check valve in the fuel pump, faulty fuel pressure regulator, leaking injectors or leaking fuel lines, including those inside the tank.

Turn the key to "on" several times, rapidly. See if it starts faster after doing that.

 

Ill get the pressure tester from a buddy tomorrow and check it. Should
I let it sit awhile and see if the pressure drops. I think its suppose to be
around the 40-45 psi mark.

 

I was dreading the FP replacement if needed,until I saw the access door thread,thank goodness.

 

Did a fuel pressure test and it as around the 36-38 psi (max 40) range and would drop when I hit the throttle. I believe that is way to low. What do you guys think?

 

Yes, that's too low if you tested with the vacuum line off the regulator and plugged. It might be OK if you tested with the vacuum line on.

What you were looking for, however, is if the system holds it's pressure when the pump is off. To test that you hook up the pressure gauge with the engine off and prime the system, either by turning on the ignition or with the prime connector on the pcm harness. Then you turn off the power and watch the gauge. If it holds pressure the regulator is fine and the starting problem is elsewhere. If it doesn't the problem is either with the regulator or with the check valve on the fuel pump.

You can have a bad check valve and still have the car run fine. This is because the pump is able to supply the correct volume of fuel at the correct pressure....

 

Ah crap,knew I forgot something,I left the vacuum line on. Ill check it again when
I get home later. I assume that the gauge should go
Up when I unhook the vacuum hose from the regulator?

 

It should be in the range of 41 to 47 psi....

 

The vacuum line being on or off only makes a difference at idle and part throttle. 36-38psi with it on, at idle and during part load is fine. 41-47psi is the GM spec without the vacuum line. But when you go WOT, there is not really any significant vacuum, and the pressure should never drop below 40psi.

 

Going to verify the readings from earlier,but I believe when I had the throttle wide
Open it was dropping to around 35 psi. Ill leave the gauge connected and see
If the psi drops and how fast.

 

Did some more tests...

(1) Prime system at let it set for 30 mins....started @ 16 psi and stayed there
(2) Car @ idle > It stayed in between 30-34 psi,removed the vacuum line and it stayed @ the 30-34 psi mark
(3) Car running and popping the throttle,would actually start dropping to around 20-25 psi
(4) WOT stayed constant at 25-30 psi

 

Ok guys,do you think it's the fuel pump?

 

My 94 was doing the same thing for a while it was stock I replaced my pump and it took care of it car had 75000 on it when it started

 

Thanks,I just hit 94k. Since the pump is fairly cheap and it won't be such a pain,I probably will just go ahead and replace it.