[dilsingh]

I have replaced the engine mounts and the transmission mounts on my MY2000, E320. The engine is very quiet when in N or P, but I have a vibration when stopped in gear with foot on the brake. I noticed thathe RPM drops to around 500 vs around 600 in N. If I press the accelerator very slightly while stopped with the foot on the brake the vibration disappears at around 600-700 RPM. Does this mean that the idle speed is too low for the engine in gear and stopped with the brake ? Can something be done to fix this problem ? Is there a DIY or ideas to investigate ?

 

[illest]

Could be several things. Check your motor mounts.

 

[fabbrisd1]

There are a LOT of W210 knockoff China and India motor mounts out there - attractive on price - that are worth sh*t - and often start failing in 3 to 6 months...

Lemfoerder or MB brand mounts are the only good ones

 

[dilsingh]

Guys the motor mounts I have used are original -- from Autohausaz. My motor mounts are fine as evidenced by the quiet, vibration free car when in N or P. The problem is with the car being in any gear D or R stopped with the foot on brake. With the foot on brake a slight increase in RPM causes the vibration to go away. I have also changed the motor mounts also from Autohausaz without any change in the problem. The RPM is governed by the car computer, but I ma not sure if it can be set to a different speed at idle. I think if I could change from around 500 to say 650-700 the vibrations would go away. The RPM drops a little ( from that at N or P ) when in gear and car stopped by the footbrake.

 

[Check Codes]

Where did you buy the trans mount? The one autohausaz sells is URO junk (not to be confused with Euro Trash).

Idle speed sounds about right but if you're concerned it should be verified as the tach in the dash is electric and may be affected by mild voltage fluctuations (which are more likely at low alternator speeds).

If when gently releasing the brake you can kind of feel a surge, then replace your plus with stock ones (unless you have done that) and test/inspect your ignition wires while changing them.

Good luck.

 

[dilsingh]

My engine mounts are Lemfoerder and the transmission mount is Corteco ( OEM). Engine mounts from Autohausaz and the transmission mount from Partstrain (?). I do not feel any surges. I am going by the Tachometer in the dash. Is there a way to increase the idle speed ?

I changed my spark plugs with the stock ones about 20,000 miles ago. What should I look for on the ignition wires ? A new set is about $150 and I am not sure if there is an interval at which these leads should be changed.

 

[dilsingh]

I think my ignition leads are OK. However, my experiment with increasing the engine idle speed with more tension on the accelerator cable did not help to increase the engine speed when in D or R ( stopped with foot on the brake ) ? Any suggestions ?

 

[nford]

Its worth checking rear subframe mounts,if they are gone it can send vibration through the car

 

[SkippyJasper]

Are all of the rotating devices on the front of the engine OK?
When my water pump bearing was failing there was a rubbing sound at low rpm's. That disappeared once underway.
Skippy

 

[tirona]

try cleaning the throttle body and see if that helps. throttle cleaner spray and a rag or old tooth brush is all you need, but make sure you open the throttle slightly to clean as much as you can inside of it also, but don't drop anything in there

 

[dilsingh]

I cleaned the throttle body and applied Seafoam to the fuel without any success.

 

[MeMySelfundIch]

since I have the same problem with mine, and I also replaced my mounts (Motor and Transmission) with original Benz stuff (bought at the stealership..) and I have a very low "bassline" throbbing wenn idling with the brakes at the light - I am very much interessted in the solution to this.

any more Ideas? What bushings from the rear frame do you mean? Can you post a picture?

 

[dilsingh]

I beleive the problem is related to the engine speed being around 580 RPM when at normal temp and not something mechanical like engine mounts -- however, I am an EE so I think of non-mechanical things first. My next step is probably to look at all the spark plugs and wires since I have not changed the ignition wires at all.. Is there a good way to check these rather than blindly replacing them ?

 

[KMani1]

You declare an EE, I bet you have/had a DMM you can ohm it out and the different between them should give a hint which one was the culprit, but you probably end up replace them all. If it's me I would replace as a set.

 

[dilsingh]

Will I see enough difference with a DMM to find the good and bad ones ? What is the acceptable DC resistance of these Ignition wires ? Anyway, its easy enough to try, but I am just doubtful aboiut being able to tell the good ones from the bad.

 

[KMani1]

From experience of my 95 W124 E320 the bad one was open or intermitten, the good one 750 +-50 Ohm or might be some different depend on brand but you will find out when you check all of them. Hope this help you somehow.

 

[MeMySelfundIch]

the ignition coils are sitting right on top of the sparkplugs.. what wires do you want to change?

are the V6´s different to the V8´s ?

 

[tirona]

any more Ideas? What bushings from the rear frame do you mean? Can you post a picture?

i think he is talking about the subframe mounts, #2 and #3 from diagram 2001 MERCEDES-BENZ E430 Parts - Direct BMW and Mercedes Parts and Accessories
this is a pretty good thread from stickies http://www.benzworld.org/forums/w210-e-class/1488483-diy-rear-axle-carrier-mount-rear.html

but i doubt the subframe mounts are bad in your car, since they should easily last about 15 years/200k miles. you can always check them.

 

[dilsingh]

I am referring to the wires that come from each coil ( 2 each) to the spark plugs.

 

[dilsingh]

All of the wires I measured were around 2100 - 2200 Ohms. I did not see any issues with the wires. I do note that the vibration happens after the engine warms up when the idle revs drop to about 700. Before it warms up, the engine revs are closer to 1000 and I do not feel the vibrations.