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problem with combo

  • Thread starter Thread starter 9 Deuce GT
  • Start date Start date Jun 16, 2005
9

9 Deuce GT

Member
Dec 10, 2003
550
1
16
Geneva, NY
Jun 16, 2005
#1
  • Jun 16, 2005
  • #1
I have been having a lot of problems with my new combo. All of the problems are covered in this thread: http://forums.stangnet.com/showthread.php?t=554136

I have been trying a few things. I dropped fuel pressure from 39 to 32psi. The idle got better when the engine was cold. Then, when the engine reached normal operating temp. the surging begins. I looked at the press. guage, and I noticed when it surged, the press. dropped and then came back up repeatedly. My question is, wouldn't the press. stay the same regardless of if the idle is surging or not? I am just trying to understand what exactly is going on.
 

bullitstang1313

Member
Jan 21, 2003
713
0
16
Indianapolis / Columbus, Indiana
Jun 16, 2005
#2
  • Jun 16, 2005
  • #2
Sounds to me like you've got a vacuum issue. That could be why your fuel pressure was surging along with the engine. Make sure none of the vacuum lines behind the intake were pinched when installing it. You can check the vacuum with a gage as well. I don't remember off hand where its supposed to be at but you can probably find it using the search. The a vacuum issue would affect the idle as well since the engine doesn't produce as much vacuum at idle as it does at wop. hope this helps, good luck.
 
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