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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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seriously??? a vac leak?!!?!?!?

  • Thread starter Thread starter srtthis
  • Start date Start date Sep 27, 2011

srtthis

the guy doing it does every local racers rear end
15 Year Member
Jul 3, 2009
5,129
1,666
204
Maryland
Sep 27, 2011
#1
  • Sep 27, 2011
  • #1
im sure some of you have seen the engine bay pictures from my personal car... i have 2 vac lines and a PCV line which is now plugged offand will be going away also.

have had a surging and hanging idle the last few months that i have been fighting. thought it was a result of my ported SN95 maf. put the stock one back on it. got it to idle right but it had trouble idleing down some times. pulled the IAC and cleaned it which did nothing and was clean to begin with since im not running a breather line from the valve cover and have MAYBE 600 miles on it in the last 2 years and just put the thottle body on after smoothing it out also. while it was apart i also cleaned the IAC at that time.

after unhooking the IAC thinking it was that... i got it to idle ok with the stock MAF last night. i put the ported SN95 its had for the last 2 years on and never had an issue till lately with back on... got it to idle ok around 800rpm... look at my driver side valve cover and notice oil dripped on it. right below a vac bung i have capped off. so i pull the intake off last night and notice its dry rotted, so it looks like im doing what i had planned to do from the begining and pull the bung out and tap it for a brass plug.

moral of the story...

vac caps suck!
 

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
Sep 27, 2011
#2
  • Sep 27, 2011
  • #2
Yep, I remember I had to replace mine every few weeks cause they would crack and cause leaks
 

BlackGT89

Member
Dec 16, 2002
774
8
18
Huntsville, AL
Sep 27, 2011
#3
  • Sep 27, 2011
  • #3
I just had similar problems with my car, it would die and run like crap when cold, act like it was camming and everything. The hanging idle kept getting worse and worse. I went through the usual suspects (cleaned mass air meter, cleaned the ten pins, I had cleaned the idle bypass just a few weeks ago) and nothing would fix the problem. Finally decided I heard a small vacuum leak, so I grabbed a "listening device" (vacuum cleaner hose) and located the leak under the manifold. It was the line running to the charcoal canister - problem fixed.
 
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