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Fuel pressure regulator help

  • Thread starter Thread starter prsrizdgt
  • Start date Start date Oct 29, 2005
P

prsrizdgt

New Member
Mar 12, 2004
231
0
0
St. Louis
Oct 29, 2005
#1
  • Oct 29, 2005
  • #1
A little background guys: My car has been taking a long time to crank before the engine would fire up. Then it would just bellow black smoke for 3- 5 seconds until it cleared out. After that it would run pretty normal. I thought it could be the tune since my tuner has been tweaking some final issues for me, so I had him lean out the crank fuel table in my tune. This did not change anything. He mentioned sticking injector. While thinking about that it dawned on me that with my underhood pressure gauge, I could tell if pressure was bleeding off faster than it should. Well, it was. In a matter of a minute or two, the fuel pressure would be gone after turning the motor off. When I started it, I noticed that I was only reading about 28lbs of pressure, and when I pulled the vac line off the reg., the pressure went up to 38lbs, but I am leaking fuel out of the short tube where you attach the vac line. Now, keep in mind I have an aftermarket intake manifold with an upper plenum (Eaton roots blower), and the runners are a straight shot down into the head. I think excess fuel is being sucked out of, or bleeding off thru that regulator by the supercharger vacuum line, and is pooling down into the cyl. What do you think? Its been a long time since I adjusted fuel pressure, but I don't remember ever getting fuel out of that vacuum port before.

If this is the problem, I am not real happy with Aeromotive. Anyone reccommend a differant brand regulator that will fit the stock location?
 
C

cltgt

Founding Member
Apr 15, 2001
931
0
0
Geneva, Fl.
Oct 30, 2005
#2
  • Oct 30, 2005
  • #2
The diaphragm in the regulator has gone out. I have had two areomotive fpr's do that to me. I switched to Kirban and have had no problems.
 
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