Driving 50-60 miles per hour, the car will increase RPMs all the way to the red line and car will slow down. When de-accelerating, the RPM will come down very little and the car will stop properly and can be turned off, restarted and the car returns to normal.

This happens quite regularly. I'm trying to find what the problem is and what I need to do to fix it.

Thanks for any help you can provide.

John Baldwin
281 578 9118

jb:

Does the problem occur only when the Cruise Control is engaged?

Transmission is slipping?

Sixto
98 E320s sedan and wagon

probably transmission is slipping. how many miles and when was the last time you had the trans fluid changed ? on the 2000 onwards models the transmission electornic conductor plates can be replaced and the problem is cured. not sure if your trans has the conductor plate.

__________________
Whether you think you can or cannot, Either way you're right!. by Henry Ford.

So this is a 1990 car which means it's going to have a 722.3 or 722.4 transmission in it. No electronics or conductor plate to worry about.

To clarify with the OP - is the engine running up in speed but the car is staying the same or slowing down?

Or is the engine running up in speed and the car is also increasing in speed and you have difficulty slowing it down?

If the prior, you have transmission problems - likely low or burned fluid or internal wear causing slipping.

If the latter, you need to see if you have a linkage sticking somewhere or tell us if you're using cruise control when the behavior happens.

Since the transmission is mechanical, if you're having transmission slippage then the stopping and restarting behavior is only coincidental. You pull over long enough for things to cool down and stop the slipping temporarily.

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Thanks for the advice. I am going to take it in and have the transmission fluid drained, change the filter, etc. Thanks for the on-target answers, Diseasel300. Your comments were right on..."To clarify with the OP - is the engine running up in speed but the car is staying the same or slowing down?"

I appreciate your help

John Baldwin