pmathews

I have a vacuum leak in the vacuum line manifold located behind my glovebox in my '97 C230 (4-cyl). Mercedes says they will replace the part ($40), but it will cost $450 to drop the dash to get to the part. Is there a cheaper way to solve this problem?

I'm getting a rough idle, and I'm wondering if the vacuum leak is causing a lean condition. It runs fine at normal driving RPMs.

Can I isolate the leak at the engine manifold (if anything, just for testing purposes)? I can only find a vacuum line that leads to the brake booster, and I don't want to drop this (i.e. no brakes, or very hard brakes). I've searched between the engine and engine firewall, and I can't see any other vacuum lines.

Do I really need the vacuum in my climate control system? The leak causes a whistling sound on startup, but goes away once the car has been driven for about 30 seconds. The system blows cold AC through all the vents, but if I try to redirect the air via the climate control selector, it starts to whistle again. Currently, I leave it in 'auto' and it works fine. Maybe it will stay in this position without the vacuum (acceptable). What about the door locks and such?

I've read the archives on this topic, but haven't found an answer.

Thanks a ton!

..... Paul in Sarasota

pmathews

Here's an update on the vacuum leak problem. My engine idle problem was not related to the vacuum leak; it was a mis-gapped spark plug. Now the car runs great, but I still have the whistling sound under the dash.

Any ideas would be much appreciated.

Thanks.... Paul from Sarasota