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Old 08-24-2015, 02:33 PM   #704 (permalink)
phunk
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Quote:
Originally Posted by instroke View Post
So I had Seb/Greg - load a Ecutek tune yesterday. And the first thing he noticed was my idle fuel pressure is 72 psi. And this might be causing an issue with the cranking tables. As hot start issue is still there, uggg.

But during a few of the base runs - they also noticed my fuel pressure at wot drops to 62 for a couple secs then it drops to around the 40 psi range.

8 psi got me to 478 hp/torque of 394 then did a 10 psi pull and it got me to 525 hp but it was lean - and unsafe - so they got me to back it down to 8 psi of boost. And that's where it stays until I find the issue with the fueling.

Seb/Greg recommended a fuel return system. So I know Jmac88 here does not run a return system, and he has no problems running with pressure loss.

And Mitco here does have a return system, and has had a couple fueling issues.

So how many of you guys have return systems? Do you guys think maybe I have a bad fuel pump?
Stock pressure is 52. It sounds like your fuel pump module was not properly modified to accommodate the larger fuel pump you have, and its causing a low load pressure spike. The regulator is unable to do its job during low fuel consumption. As fuel consumption increases pressure will come back down to the proper setting. Then it should hold there around 52 until you are maxing out fuel system and then pressure starts to drop again.

Do the idle pressure fix and that will solve your spikes. The return system will solve the drop on the top end.
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