TLegendGS

Supposely a quick fix to a jump idle is to spray WD40 in the vacuum line off the brake booster to help free it up. Where exactly is that, does anyone have a pic or diagram? Thanks!

hinchcliffe

What year car?

S4 has a vacuum fitting the has a Y-connection near the thottle cable assembly. Spary it into the one that head under the intake manifold. Car of of course.

TLegendGS

Same as yours, Thanks I will try that.

hinchcliffe

Glad I couldn't spell or have good grammar yesterday.

dleopard

:ROTF:

I guess I didn't notice until your note

Shark_gts

You may want to try LPS, the stuff that our local industries use.

You'll never use WD again.

Brett Matthews

That "Y" line off the manifold to the idle speed actuator and booster, while my problem may not be with that item, I've sprayed about four times, with no change in my problem..... So, I'm diving deeper into the engine, 'specially after seeing the post, where someone found a cracked/split breather (?) line....

What is/are your symptoms?

Mark Anderson

I removed hose #11 and sprayed it in the hose.
http://members.rennlist.com/v1uhoh/underthe.htm
Also look at #17 on the 3rd picture down.

Fabio421

Actually what I think you have heard about is not spraying wd-40 INTO a vacume hose. It is sprayed near or on the vacume hoses. What you are looking for is a vacume leak. That means that the engine is drawing air from outside into the system through a cracked or disconected vacume hose or some other such source. You spray the wd-40 around certain areas that have lots of vacume hoses or in an area that you suspect to have the problem. The wd-40 will be sucked into the spot that is leaking and you will hear the engine rpm raise up slightly. Using this method you can pinpoint your problem area much quicker. Some people use starting fluid instead of wd-40 but I wouldn't recomend it because it is too flamable and it can cause severe problems if used too liberaly.
Good luck with the leak.

ErnestSw

Fabio,
Welcome to the board.
WD40 can be used exactly as you describe to identify a vacuum leak, but I think TLegendGS was referring to another use for WD40. It can be sprayed into the oil breather lines to free up the idle speed actuator if it's sticking.