Monique

I cleaned my ISV 1200 kms ago... yet I have all the usual symptoms of it needing cleaning again.

So I did it. Had quite a bit of deposit and it did not budge. After cleaning with turpentine, now fully loose.

Any of you encounter an early refoul?? Was not as bad as last time but still.

JasonAndreas

You put too much oil in during your last change? The oil breather hose attaches to the intake manifold right in front of the ISV opening.

Monique

Good thought... but no cigar! No overfill.

JasonAndreas

K&N air filter? You have to be sucking oil from somewhere upstream of the throttle body for the ISV to gum up so quickly (unless I'm missing something obvious, wouldn't be the first time).

I just took a look at my engine and the lower intake manifold crossover has a slight oily film but if anything I underfilled during my last oil change and the intake manifold was removed and scrubbed clean around the same time.

Steve Weiner-Rennsport Systems

JP:

Your experiences are pretty normal depending on the engine's mileage, leakdowns and of course how much oil is in the system. Engines operated at the upper end of the RPM range do generate more oil vapors that contribute to the buildups in the ISV, however its a simple matter to keep it clean.

Its the circulating oil vapors in the tank that get pulled back into the intake to be burned and thats mostly a function of blowby.

tsjoel

I just did mine last weekend. Not too much build-up. It seemed to be working fine but will work better now. Can't imagine that 1200km would cause a normal car to clog it up. My car only has 35k on the clock so it may change as the mileage gets higher. Steve would know better than me.

Monique

For Jason: Nope either. No K&N filter. OEM Porker. I havve a suspicion ... I had to idle for a long time 2 weeks ago... think it might have come from that.

Steve: my car has 45K kms i.e 27 K miles. Not burning ANY oil. Not 1 liter in 5000 kms.

tsjoel: thks for the ideas.

Thank guys... all is appreciated!

dhicks

Sorry for the ignorance...what is an ISV???? Does it have anything to do with the SAI???

kkim

http://p-car.com/diy/isv/

dhicks

Thanks for the link...now....how often should it be cleaned? What happens if you dont clean it?

kkim

When it gets dirty, it gums up the valve inside and idle speed is low or erratic.

How often??? Like Monique is posting, sometimes often. It seems it matters how the car is used.

I'd clean it if yours has never been cleaned before and every time after that when you seem to have idle problems. Fairly easy job, but getting it off the first time can be a bit of a puzzle on how to reach some of those clamp screws.

HK G36C

I have cleaned the ISV at every oil change or 2000k. It gets dirty at 2000k....

Steve Weiner-Rennsport Systems

That is truly a capital idea,....

Rick Lee

In an attempt to cure my low idle, I cleaned my ISV, which did some dirt in it. Made no difference at all. Idle is rock solid at 500 rpms.

Brett - 1996 C4

It's also a *very* good idea to put some kind of rubber treatment on the hoses attached to the ISV. It was a real bitch getting those off the first time. Got everything lubricated. Made them easy to put back on and the second time I cleaned it out, the hoses came off a lot faster than the first time around. Forewarned is forearmed.