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86-88 GT Fuel Pressure Regulator Location?

  • Thread starter Thread starter gs5pointOh
  • Start date Start date Jul 2, 2006
G

gs5pointOh

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Apr 22, 2005
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Jul 2, 2006
#1
  • Jul 2, 2006
  • #1
Hello. I'm trying to change to an adj. FPR on my '88 GT, but can't find the stock regulator. Either I'm looking too hard, I'm an idiot, or both.

It's searching for idle briefly at start-up and occasionally stalls/searches for idle at a stop, or when you put it in park. The idle fuel pressure went from 36psi to 46psi at idle when I installed the chip and smells rich just idling. It runs wonderful when you get moving and screams at WOT, but idles like crap.

I don't want to remove the chip for that reason and hope to tune it around the chip, even though I still have speed density. Any info would be greatly appreciated! gts88fiveoh@yahoo.com
 
T

TENGRAM

New Member
Mar 18, 2006
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Jul 2, 2006
#2
  • Jul 2, 2006
  • #2
mounted to the fuel rail on the back side of the intake manifold, behind the egr valve with a vacuum line attatched to it
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
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Massachusetts
Jul 2, 2006
#3
  • Jul 2, 2006
  • #3
back side of intake...passenger side.

I don't think an adjustable regulator may help you much. It's purely vacuum operated so if the FP jumped then something changed with your engine's vacuum at idle.

Are you still running speed density? Is the chip designed for that?

Fuel pressure settings are really only for WOT. At idle and part throttle the EEC reads the 02's to determine if it needs to open or close the injector pulse width. If you bump pressure, it will shorten the duration.
 
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