falling fuel pressure

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Sep 20, 2013 | 12:28 AM

derekbuckner1

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From: West Virginia

falling fuel pressure

I recently put a racetronix pump in my car. Before, the stock pump was hit or miss. At times, it would work just fine but other times I would get no pressure at the rails. The problem got worse, so I changed the pump. With the new racetronix pump, I noticed it took longer to prime but didn't think much of it. The car has never failed to start. I wired in a fuel pressure gauge tonight and the fuel pressure goes to 60 when I key the car on, but falls to zero within just a few seconds. With the car running it holds at 60 with no problem

I'm trying to determine whether the new pump has a bad check valve or if it's my regulator. How can I locate my problem?

I may be completely wrong, but I had the mindset that a bad regulator would leak pressure slowly, but my pressure drops to zero in a matter of two-three seconds. Any advice would be great.

Thanks

Sep 20, 2013 | 03:58 PM

never2low

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From: Brookings, SD

Not to hijack but, I would like to know as well. Ive been fighting this exact same problem for the last couple of weeks with my Lonnies dual setup with maybe 1500 miles tops on it.

Sep 20, 2013 | 08:41 PM

man-o-war

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From: Palm Beach FL

Regulator is probably leaking back into the tank

Sep 20, 2013 | 09:18 PM

haulass350

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From: Savannah, GA

i just had this same problem they sent me a walbro with the brass fitting on the top, mine doesnt need it, and it was spewing out fuel form that fitting and i was loosing pressure at WOT and it would take forever to prime up, pulled the pump back out and blocked the fitting and all is well now.

i had to get the g/f to switch the key on while i watched the pump prime before i could figure out what the problem was, make sure you have some good safety glasses lol

Sep 22, 2013 | 02:48 AM

derekbuckner1

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From: West Virginia

Found the problem. The clamp where the flex tube connects to the top of the housing wasnt sealing up and was allowing fuel to leak out from there. put a new clamp on and it no longer leaks. Unfortunately I have one more question. Previously the fuel pressure would prime up to 60 and rapidly drop. Now it primes to roughly 49psi and holds. Still seeing 60 when running. Is this normal? Want to make sure before I hook everything back up. Thanks.