Jake linked the vid in the other icv thread you'll find right next to yours.
The lower intake boot, if cracked, causes unmetered air to enter engine and the car doesn't know where it came from, coz the maf (mass air flow sensor) didn't register it, so it will add extra fuel to compensate and you'll run lean...at some point, this may trigger 02 sensors who see lots of unburnt fuel, coz mixture was bad...and you'll get the CEL...and if unattended, will end up shortening the life of your cat.
There are a number of vac lines around...one runs the instant mpg gauge in your car, others work in the emissions control system...and I'm sure there are others too...but don't quiz me...would be guessing even more! LOL
Oh...this air filter you have...is it an oiled kind? If so...don't seem to like all the stories we hear about them messing up the MAF...so clean that.
And finally, since we had a guy blowing up his intake manifold...after you clean the icv (remove to clean!) let it dry thoroughly before starting the car...and don't spray TB cleaner into TB...either just wipe with a rag with cleaner on it (parts or TB cleaner) or remove it and spray it well. Assuming you didn't plan to do TB...I think I'd prolly leave it on...or search for whether guys seal it with touch of rtv. You want all that stuff on intake side sealed...and that might be the vac leak you're talking about...air can suck into through the disa, I know (again, unmetered air) coz there is a vacuum inside engine...slight, but enough to suck in air...so get things sealed up well is all I can say. If you can, pull things off and replace rubber behind...if you have a car that drives to go and get what you need from dealer...which may or may not have these things...suspect they prolly use rtv...but don't know if they'd use anything at all.
Last edited by dmax; 11-07-2010 at 06:01 PM.