Possible leak in vacuum advance system/rough idle and car shakes
 

Hey guys im new to the forum but have had my 2001 mercedes e430 for about 6 months now but about a month and a half ago i started my car to leave my house and the engine ran really loud and the rpms shot way up but went to normal after the car got to normal temp i just changed the oil 3 days ago and it was warm today and took it for a drive and the car ran fine 2 hours later on my way to work i stoped at a red light and my car did it again it sounds like the engine is running hard i wanted yo know if it will hurt the car to run it like this until i can get it fixed in 2 weeks or if i should park ot and wait i do have another car i can use so i dont need to run it if i dont need to but was curious if it will harm anything and idk if it means anything but the car does have 168289 miles on it but other than this it runs great

I did check my motor mounts so there is nothing wrong there any advive at this point is apprciated and how much it may cost to fix thanks all

i wouldn't continue driving it in that condition, nor would I gamble on your finances by sitting at my computer
and relying on your description of the sound. the potential cost to repair an engine can be severe. get codes
pulled. sound and engine revs changing sounds like sensor and mechanical combo. it's silly to suggest a
repair cost based on the barest of factual data.

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I do have a guy coming to look at it next week i told him everything its been doing and he thinks a vacuum leak i have talked to a lot of mechanics that are benz certified and they all say the same thing its a vacuum leak of some kind

That sounds wrong. Vacuum leaks don't come on and off. they are steady and do effect idle performance, but not just sometimes.

I just bought my E430 back in October, it also had the butt shake at idle. I hooked it up at work and found that a couple of the ignition coil wires were no good. Swapped out and shake went away. definitely get it scanned so you know exactly whats wrong though.

I have a e320 (1999) that runs well but seems to be rough at idle in D. I wonder if the coil wires are bad, do you get a light(check engine)? Also if I only have an OBD2 style scanner will I see the coil wire codes? Thanks in advance.

I dont think so but dont hold me to it. We have a computer here that can read the values of each coil and see where the problem is.