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Made in USA
08-14-2014, 06:54 PM
I'm on my 4th one now. Any ideas why?

I've discussed with Marc H and he has never heard of this problem. When it fails, it leaks fuel back through the vacuum line, into the plenum, and all over the floor.

I'm changing the vapor canister just because, and I also put a new gas cap on.
weldbead
08-14-2014, 07:32 PM
wondering if you know how this regulator works?i had a different style on my '91 L98..no vacuum..i swapped it out for an adjustable on from midamerica..c4koh noticed that the vac line on mine had come off, i didnt notice much difference when i put it back in place..of course i think i have a large secondary vacuum leak which may be affecting fuel pressure regulator..
LGAFF
08-14-2014, 07:35 PM
What fuel are you running and anything you are putting in it?
LGAFF
08-14-2014, 07:39 PM
Wonder if your return line is blocked causing high pressure???
Made in USA
08-14-2014, 07:41 PM
What fuel are you running and anything you are putting in it?

I use Conoco 91 octane exclusively. Almost any other fuel and it will ping. I don't use any other additives.
Made in USA
08-14-2014, 07:43 PM
Wonder if your return line is blocked causing high pressure???

I was wondering about that too. Is the return line a direct shot back to the tank ?
LGAFF
08-14-2014, 07:45 PM
Wonder if the canister is pushing gas into the intake and not the regulator
ZZZZZR1
08-14-2014, 07:46 PM
I'd wonder if it has anything to do with the fuel rail?

Is that connection not tight enough?

:cheers:

David
LGAFF
08-14-2014, 07:49 PM
When you put a fuel gauge on the rail does it hold pressure or bleed off? Ever test Fuel Pressure under load??
LGAFF
08-14-2014, 07:50 PM
https://www.youtube.com/watch?v=AKtR_yF7bi8
Made in USA
08-14-2014, 07:51 PM
When you put a fuel gauge on the rail does it hold pressure or bleed off? Ever test Fuel Pressure under load??

It holds pressure. I've not tested it under load other than at idle.
Made in USA
08-14-2014, 07:52 PM
I'd wonder if it has anything to do with the fuel rail?

Is that connection not tight enough?

:cheers:

David

The fuel rails have been off several times. I don't think they are the issue.
Schrade
08-14-2014, 08:07 PM
Can you get a vid of the gas dripping out of the FPR vac port nipple?
Made in USA
08-15-2014, 01:23 AM
Can you get a vid of the gas dripping out of the FPR vac port nipple?

It's fixed now. I just want to keep it from happening again
Schrade
08-15-2014, 02:17 AM
It's fixed now. I just want to keep it from happening again

Cool.

But exactly what was going on there? Where was the fuel coming from?

Knowing what might happen with others is good yUp!
Made in USA
08-15-2014, 11:51 AM
Cool.

But exactly what was going on there? Where was the fuel coming from?

Knowing what might happen with others is good yUp!

The FPR is failing internally, allowing fuel to move from the supply side back into the plenum through the FPR's vacuum line.