grossesexy

Alright so I've been having hard start problems now for about a week. Car cranks a good 5-10 times before finally starting. If I prime the pump, switch to off, then try and start it the engine kicks right over or takes 2 cranks at most.

Changed the fuel filter earlier this week hoping maybe that's all it was. The problem persists. Hooked up a fuel pressure gauge and with the key turned to ON the fuel pressure is 40-41 psi while the pump is active, then slowly drops off.

When the engine starts it goes back up to 40-41 psi, and stays there. However the pressure is constant whether it's idling, half throttle, or WOT. I did about 5 WOT passes to make sure of this. So constant 40-41 psi of fuel pressure regardless of throttle.

So somebody confirm or deny this for me, I'm thinking fuel pump but I really don't know. If you want to tell me it's just my injectors doing something funny on startup I'd love that but I'm prepared for the worst.

Oh I should add the car runs fine once it starts. Idle is fine, car doesn't just die at any RPM, nothing of that sort, just has the hard cranking.

shoebox

Seems like your pump may be putting out ok pressure, but the regulator might not be doing anything. If the regulator was leaking into the vacuum line, it could cause hard starting due to an over rich condition. Remove the vacuum line and check for fuel or the smell of fuel. If there is either, replace the regulator.

grossesexy

That would be great if that's all it is. I'll try that shoebox, thanks for the input.

grossesexy

Ok now that I look at this....how the hell do I get to that thing?

shoebox

Just reach around the backside of the engine with your left arm. It's not as hard as you think.

mdacton

how fast does the pressure leak down?

I would check that regulator but seeing as when you prime it she fires up sounds like the one way valve in the top of the pump.

But check the reg. first for sure.....also check the FP with vac. off eng. running and see what happens. Then shut it down and see how fast the pressure bleeds off

dangalla

this is what i was thinking also, i have seen this a few times

mrmint69

The pressure should hold for a while. Mines 30 minutes before a slow bleed down reaches 0 in five minutes. Some hold for much longer. The FPR and fuel pump would be the obivious choices. The bladder on the regulator sounds like it could be bad.