Cleaning throttle linkage
 

My 89 300E seems to hold the velocity of the car even when lifting the gas pedal. I'm used to almost the throttle closing and resulting in some deceleration. Anyone else experience this?


It is not horrible like a sticking throttle, but just doesn't decelerate when lifting.
I am planning on cleaning the whole linkage under the filter box.... Anything else I should look into ?

I need to do the same thing to my 300E.

Not sure about your car, but my 126 has a deceleration microswitch. There is a switch that should be engaged when you let your foot all the way off the accelerator. Deceleration is supposed to begin 1 second after this switch is activated.

On my car, this switch is located under the hood near the throttle linkages, right by the intake manifold (if I recall correctly).

First, make sure that the linkage is adjusted correctly and that the switch is getting fully depressed when the accelerator is at rest.

After that, pull the wires to the switch, hook up your meter, and verify that it's turning on and off.


Good luck!

What a coincidence. The same thing happened on our 300TE, except it accelerates by itself. Took the air cleaner out, took the throttle linkages out and cleaned and lubricated the ball joints thoroughly. Also cleaned the lever mechanism and adjusted the throttle cable and transmission bowden cable to reduce slack. As with the throttle linkages on my 300D, I used white lithium grease on the ball joints, the rollers and the bushings.

Now the car drives wonderfully and has instant response, and has no more self acceleration.

Can't say enough how cleaning and lubricating it positively affected my accel and decel. The linkage is connected to the transmission, throttle body, micro-switch, and of course the throttle cable. It's been well designed but must move freely to work perfectly. ;) Besides, it's one of the cheapest things you can do for your car...

http://www.peachparts.com/shopforum/showthread.php?t=137129&highlight=idle