CIS inj. boot cracked- how bad is this?
 

Found a fairly large crack in my cis inj. boot on the top of the engine. Would this create a lumpy idle? What are the possible other symptoms this can/ has created for anyone else?


(ordered one but not sure if it's ok to drive like this- too lean?)

Harold

79 911 sc 3.0

Harold -

how bad is the crack? does it go all the way through the rubber? If so, it's allowing unmetered air which would cause a lean condition. At the least, poor running. At the worst, well, the engine can run hot, leading to damaged pistons & stuff.

hasnt run hot yet. It's all the way through though and I tried to fill it with some epoxy to help it. may have been like that for a while? How bad should it be running.. I think I had to richen the fuel mixture a while back to smooth it out.. guess that couldve been why?

Thanks again
Harold 911 sc 3.0

Can I richen the fuel some more to help compensate for the big crack in the boot? Or just leave it...seems to run ok when warmed up..

Harold

Personally, I would not adjust to compensate, Harold. I would take the boot off, clean it real well, and use some RTV or silicone sealer to seal up the boot. While you are at it, you might look for other air leaks. I'm wondering if that boot cracked from old age, or it it suffered some sort of trauma - like a backfire, which may have caused other damage, as well.