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Fuel Pressure Too High

Hanaldo

By Hanaldo,
in Engines & Forced Induction

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GTSBoy Grand Master

GTSBoy

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I would say, on the basis that the tests you have done so far are likely to give the highest possible fuel pressure you will ever see (cold weather, cold fuel, brand new pump) that you could get away with setting it just barely higher than it runs naturally. So maybe 63 or 64 psi. I would say that you are dead unlikely to get any more than you already are, and even if you did it would only be 1 or 2 psi, which would hardly ruin anything for you (richer is safer anyway).

As long as the reg and the fuel pump can keep that pressure stable across your whole operating range you should be gold.

As to your question about whether the loop you have in your line is causing any restriction....I would suggest not. Unless the hose is quite severely closed down it will still not have anywhere near as much restriction as the reg itself.

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Hanaldo Grand Master

Hanaldo

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.... wait for it.

My bet is that you have an air bubble between the fuel an gauge. Due to the orientation of your gauge.

Cheers

Justin

Which has only manifested itself as an issue now, after installing a bigger fuel pump? After running without issue for over a year on the old pump setup?

89CAL Grand Master

89CAL

Posted
Posted

Air is more compressable then fluid, and would make the gauge read lower if anything. So that is not the problem

So restriction or FPR issue I say. I would pull the FPR off and just have a look at the ports and everything just in case theres something silly going on there

Hanaldo Grand Master

Hanaldo

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Posted

Might have found the issue! Pulled the regulator off last night and had a look at it, but couldn't see anything out of the ordinary. So then I had a look at the piece of return line that came off the regulator and looped around the fuel filter and spotted this:

431226_10151483541942541_708608272_n.jpg

There's some sort of restrictor in there. Makes me wonder where this hose came from, I never purchased any hose with a restrictor in it. In fact from memory I actually just reused the standard return line, though surely they don't have a restrictor in there? Amazes me that it didn't cause any problems until now. Anyway, haven't had a chance to check whether I can lower the fuel pressure now, will finish installing the ethanol sensor and put it all back together and report back!

Hanaldo Grand Master

Hanaldo

Posted
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Yeh, me too... Wondering if maybe this caused some of my power issues, but I don't think so. Tuners never mentioned fuel was a problem, and it wouldn't have affected response anyway. In any case, I'm sure it wasn't doing any good, so I'm glad to be rid of it!

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