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Vacuum Pressure at Fuel Regulator

  • Thread starter Thread starter k00ksta
  • Start date Start date Sep 23, 2008

k00ksta

Member
May 13, 2007
158
0
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Chicago
Sep 23, 2008
#1
  • Sep 23, 2008
  • #1
I am still having issues with my car here after getting the timing set to 10* BTDC and making sure all vacuum lines were sealed and I believe routed correctly the car I believe is running way to rich. If for instance I start it and run it for a few minutes it runs decent but I do get some light puffs of exhaust smoke out the exhaust occasionally. then if I shut the car down and say 10 minutes later try to start it again it just cranks over. When I pull a plug it is wet with fuel so im starting to think my fuel pressure regulator (which is still stock on my motor) is not going to work with my setup anymore. Does anyone also know how much vacuum you should have at the fuel pressure regulator and what is a good way to test to see if the vacuum is either to strong (not sure if that matters) or is to weak. Let me know what you guys think, thanks.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 23, 2008
#2
  • Sep 23, 2008
  • #2
The FPR has a dedicated vac source and sees manifold vac. You should see about 18-20" hg at idle on a stockish motor.

If you pull the hose and put your finger over it, it'll suck your finger down pretty good. If that hose does not have constant vac at idle, some lines might have been crossed and that would lead to it running like poop at certain times.
 

RIO5.0

15 Year Member
Feb 16, 2001
6,892
8
128
N.H.
Sep 23, 2008
#3
  • Sep 23, 2008
  • #3
What he said... You can buy a vac gage at any parts place for 15.00 or so..stick it on the line that feeds your FPR and see what it pulls.... If decent I would suspect the regulator is shat or poop...
 

k00ksta

Member
May 13, 2007
158
0
17
Chicago
Sep 23, 2008
#4
  • Sep 23, 2008
  • #4
I could smack myself right now

Well .. As I was putting my Upper intake back on the motor due to taking the top half completely down trying to tripple check for vac leaks or bad gaskets I just so happend to notice that the EGR Valve looked pretty close and snug to the upper intake manifold. So to my surprise I took the 2 screws out and what in the heck do you know .. NO DAMN GASKET! so basically it most likely has been sucking air into the damn thing causing hell with the A/F ratio and the computer just has been fighting it all along. Hopefully this will take care of a few issues I got going here. I cannot believe that some how I missed that. I have torn the top half down many times but usually just pull the upper intake with the TB, EGR, and Upper intake all together .. A lovely 1.99$ gasket could be the solve to this. We shall see. Thanks for the responses once again guys.
 
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