[boonjh]

After washing out my garage (concrete floor) and parking my car in it over night, I have noticed that the next morning my car would idle very rocky / uneven. I usuallly have to switch the engine off and restart once or twice before it would go away. Sound like serious misfire or one or more cilinders not firing????

Any idea what could cause this. Could humidity do this / condensation???
Thanks
Jan

 

[beef1020]

Is your check engine light on, if so get the codes pulled.

 

[GA-e46]

I recently had the same problem, it was due to a vaccum leak. I knocked off a hose connected to a small air pump next to the Valve Cover when I changed my VCG. The rubber hose connections are very brittle after 10 years. My car was fine until it rained and idled extremely uneven. Once I replaced it everything was fine.

 

[boonjh]

No engine lights come on when this occurs. Thanks for the tip "GA-e46". I'll look around a bit

 

[boonjh]

Could this be a leak in the VCG??

 

[beef1020]

Could this be a leak in the VCG??

It could be lots of things from intake leaks, dirty idle control valve, bad coil... that's why the codes are helpful.

If you don't have codes I would check around the intake track for leaks/holes. check the lower intake boot, may clean the ICV.