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running wicked lean now...

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Nunyas

Nunyas

Yoda
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I changed out my EGR valve and gulp valve this weekend, and developed a mysterious vacuum leak somewhere. I tried to find it by spraying some WD40 in the surface mating areas of the parts that I changed but that had no effect on the idle. I have to run with the choke partially pulled to keep the idle even.

When I changed my EGR valve, I used the gasket that came with it. I did not use any gasket sealing goop when I put it on though. Should I have used gasket goop there?

Is WD40 too "heavy" to use as a vacuum leak finder? The last time I searched for vacuum leaks I used carburetor cleaner, and instantly found the source of my uneven idle.

I also installed the last piece of heatshield I was missing onto my car. It required me to remove the nut between the front exhaust port and front intake port. I didn't have to remove the manifold just the one nut. I'm pretty sure I got it back on tight enough...

I thought I'd have a much better running car after changing and installing these parts, but it seems it had the opposite effect. Should I go back and check for leaks again using carb cleaner?
 
Hi Nunyas,
Assuming that you did not miss a chunk of gasket (I know you didn't) have a look at where the gulp valve fitting goes into the intake manifold (mine was sucking air there like crazy). If no luck try removing the vac lines one at a time and plugging to se if there is a big diff, maybe one of the units has a bad diaphragm. Good luck, got to hate air leaks....they suck..
Cheers Ric
 
*light bulb* When I was replacing the Gulp Valve, a chunk of hardened goop chipped off the mounting bracket bolt (the bolt that holds the Gulp Valve mounting bracket to the intake manifold)... but there was no change in idle when I hit the area with WD40...

*grumbles* I think I'm gonna pick up some carb cleaner to tag the possible problem areas again...

Would regular 'ole blue gasket goop be good enough to seal the gasket surfaces on the intake manifold?
 
Switch to "Super" blue goop: Permatex Hylomar HPF for intake related stuff. RTV reacts to gasoline, Hylomar is impervious to it. THIN film of it is all ya need.

"Second Opinion", please Ric?
 
Personally Doc, I really dislike the blue stuff, I am a steady user of the non-setting permatex. Mind you on some engines the blue stuff would not show!!
Cheers Ric
 
Hylomar *is* a non-setting Permatex product.. and it's... mmm... blue.

Best of both worlds? I think it's a shade off Ford blue, tho.
 
Some silly b a s t a r d put this red engine togheter with the hard kind. Would really like to shoot him.
 
Yup. THAT stuff is as antique as a cast iron corset. Too many good sealants and adhesives out there now to use that cement on automotive applications. Hammer, chisel and dynomite are de-facto "gasket scrapers" necessary with it. BAH!
 
And when if finaly comes apart half the gasket is on each side, it splits right down the middle and must be ground off with one of those bursh pad kind of things.
 
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