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Chasing a vacuum leak

  • Thread starter Thread starter Skoobie
  • Start date Start date Nov 28, 2004

Skoobie

Damn...Tyler65's hot!
May 25, 2003
655
0
17
Vancouver, WA
Nov 28, 2004
#1
  • Nov 28, 2004
  • #1
Well I got it all back together and took it for a spin and I still think theres a vacuum leak. I can hear a sucking sound in 4th at midrange rpms that get louder as I accelerate. Also the idle has trouble settling down and I seem to be sans some power. I just replaced a broken upper intake bolt and the upper intake gasket. Im pretty sure I got all the connections back on correctly. You cant hear any sort of leak at idle. So is there an easy way to test the system for a leak or do I need to start replacing all the hoses?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Nov 28, 2004
#2
  • Nov 28, 2004
  • #2
a vac gauge helps. stockish motor should pull 15-20" at idle (i pull 19.5). i think you are on the right track - a vac leak will make the idle hang (and slow the return from higher revs).

a vac leak can be heard upon heavy deceleration while in gear - manifold vac can go over 20".

some use the old WD-40 around vac lines trick - if the idle changes, there is a leak where you sprayed. be careful of possible fire hazzards while doing such testing (many products are flammable).

good luck.
 
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