EJ, swapped in a cx motor with 90k on it...kept the b7 intake manifold cuz it was bigger, b7 gasket. when it warrms up and idles, it goes from 1000-1400/1500, immediately back down, immediately back up, etc. i think it's a vacuum leak, i overtightened my IM and was burning coolant, so i loosened them and that solved the problem, but my idle is still messed up. could i use high-temp gasket maker on the IM? i would imagine this would solve the problem. i have a new fuel filter and i really doubt it's a blown headgasket because the owner said the motor worked great when he pulled it. intake is not blocked, and is secure.

 

Try spraying around with some carb cleaner to determine if it is in fact a vac leak before you do anything else.

 

Have you bled the cooling system after you did this? If not, try that first.

 

how would i determine if it's a vacuum leak by spraying carb cleaner? i bled the cooling system and it's still doing it. my uncle, who is a mechanic, advised me to take it to a shop that connects my intake to a smoke machine of some sort...but it will cost $60-$150 and i really don't want to spend that kind of money.

 

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If there is a leak it will suck up the carb cleaner and idle well.

Try covering the iacv and fitv holes in the tb to see if that kills the engine, if not the air is getting in somewhere.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SVOboy &raquo;</TD></TR><TR><TD CLASS="quote">If there is a leak it will suck up the carb cleaner and idle well.
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It will make the idle surge or at least change enough that you'll know if it's getting sucked in.

 

In my case it made it idle normally, but I had a huge *** leak all in one spot.