Hello all, thanks for taking the time to read this.

I have a '99 2500 with a VA V5, no codes, runs fine when once it's started. My LP pressure fluctuates occasionally and I have a FASS HPFP to replace it.

But I have a question - can a flakey LP cause hard starts? When I turn the key to the run position and the LP primes, I see 13 psi, it cranks @ 10 psi but takes about 10 or so revs of the engine instead of 1 like normal before it fires. It seems to be most of the time. But if I let it sit for 5+ minutes, It cranks much longer than it normally used to. Fuel pressure seems normal but on occasion will bounce to 6 and back up to 11 so I know the LP is on it's way out. It's always had good fuel pressure.

What about the diaphragm in the VP I keep hearing about? Is that supposed to hold the 'prime' charge in? Or if my LP is flakey could that be it?

Thanks for the help.

Mike.

 

is this on a hot or cold engine? hard starts on a warm -hot engine could be a bad diaphram causing it. have you tried unhooking the V5 to see if that helps?

 

Thanks for the reply. Actually, I haven't tried that but I will.. on the way home the CE light came on and I got an 0336 for crank position sensor. The truck will act the same warm or cold. It does act kindof sporatic, though. I don't have white smoke, there's good fuel pressure, and it runs great. Do you think the CPS could cause that problem?

Thanks, Mike.

 

Very good possibility on CPS. Good luck getting to it.