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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Adjustable Fpr & Gauge

  • Thread starter Thread starter RangerJoe
  • Start date Start date Aug 27, 2012

RangerJoe

I leave the horn on while driving
15 Year Member
Apr 26, 2010
2,560
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184
Georgia
Aug 27, 2012
#1
  • Aug 27, 2012
  • #1
Hey guys,

I installed a brand new Kirban adjustable FPR about a year and a half ago. At the same time I installed a gauge on the pressure relief valve, I think also made by Kirban (came for LMR). I noticed right away that when I made changes to the FPR, the gauge was very slow to react. I would have to make a turn, and wait about 3-4 minutes for the gauge to adjust its reading, then make another adjustment if that wasn't enough.

I set the gauge to 39 psi and forgot about it, until last weekend when I installed 30lb injectors. The car smelled richer than normal, so I tried to turn the pressure down to 35lbs. The gauge did its normal slow response, but finally registered the change in pressure.

So, is this normal? My fathernlaw seems to think the guage should respond almost instantly. If this isn't normal, do you think it is the gauge, the FPR or the fuel pump being weak (no other signs of that going on).

Thanks,
Joe
 

tca7291

I can see your wieners.
5 Year Member
Sep 1, 2011
1,801
152
143
Raleigh, NC
Aug 27, 2012
#2
  • Aug 27, 2012
  • #2
It could be the schrader valve in the fuel line port. After working A/C for 8 years, I've experienced those little valves go bad in the sense that they won't open up multiple times, and that kinda sounds like it could be your problem.
 

RangerJoe

I leave the horn on while driving
15 Year Member
Apr 26, 2010
2,560
1,146
184
Georgia
Aug 28, 2012
#3
  • Aug 28, 2012
  • #3
Is the schrader valve on the fuel line specific to the fuel line, or can I use a generic replacement?

Joe
 

tca7291

I can see your wieners.
5 Year Member
Sep 1, 2011
1,801
152
143
Raleigh, NC
Aug 28, 2012
#4
  • Aug 28, 2012
  • #4
That is a good question that I don't know the answer to, but if you have your fpg on it semi-permanently, then you could just release the pressure, pull the valve out and reinstall your gauge (leave the valve out).
 

Dino Dino Bambino

15 Year Member
Jun 13, 2007
1,673
90
79
Cyprus
Aug 28, 2012
#5
  • Aug 28, 2012
  • #5
RangerJoe said:
My father-in-law seems to think the gauge should respond almost instantly.
Click to expand...

He's right. It should. You may just have a lazy gauge.
 

RangerJoe

I leave the horn on while driving
15 Year Member
Apr 26, 2010
2,560
1,146
184
Georgia
Aug 28, 2012
#6
  • Aug 28, 2012
  • #6
Thanks for the response guys. I'm going to try removing the schrader valve and see what happens. If no change, I may try to pick up a cheap gauge somewhere just to try out. This gauge was the more expsensive one that was recommended (well of course it was, it cost more) by the sales rep.

Joe
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Aug 28, 2012
#7
  • Aug 28, 2012
  • #7
purge the line first
 
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