Vacuum leak 89 325i

[Afredo]

hey guys, I have a slight hesitation between 2 and 3k RPM, figured it was probably a vacuum leak so I did a smoke test Smoke appears to be leaking from the valve cover and from the connector of the idle control valve. When I bought the car this past march I replaced the valve cover gasket and rocker plugs, so the only reason I can think that the cover would be leaking is I didn't torque down the valve cover bolts, just snugged them on there. Sound like it could be the problem?

And the IAC leaking, would it be the IAC unit itself that needs replacing, or the connector, or both? Thanks!

[DooDanE30]

well if its leaking from the valve cover that is an easy fix. there are a number of reasons why its leaking. could be that you didnt torque it down tight enough or that you bought one thats defective or you bought an aftermarket one or something. Point is theres not headache there because its so simple to replace.

[Afredo]

well if its leaking from the valve cover that is an easy fix. there are a number of reasons why its leaking. could be that you didnt torque it down tight enough or that you bought one thats defective or you bought an aftermarket one or something. Point is theres not headache there because its so simple to replace.

ok I figured as much. What about the vacuum leak from the IAC?

[jlevie]

The elbow fittings that were pressed into the throttle body can loosen with time and cause intake leaks. The best fix for that is to remove the elbow, clean the nipple and socket with acetone, and use JBweld to reattach the elbow. Allow the epoxy to cure overnight before starting the engine.

[Afredo]

The elbow fittings that were pressed into the throttle body can loosen with time and cause intake leaks. The best fix for that is to remove the elbow, clean the nipple and socket with acetone, and use JBweld to reattach the elbow. Allow the epoxy to cure overnight before starting the engine.

yea they did pop out last time I was fiddling with the intake tubing, wasn't sure if they were supposed to come out of the throttle body or not, now I know. however, when I did the smoke test the smoke was coming out of the IAC motor where the sensor clip connects. do I need a new IAC new clip or both?

[Afredo]

bump

[jlevie]

yea they did pop out last time I was fiddling with the intake tubing, wasn't sure if they were supposed to come out of the throttle body or not, now I know. however, when I did the smoke test the smoke was coming out of the IAC motor where the sensor clip connects. do I need a new IAC new clip or both?

Sounds to me like you need a new IAC.