nine

I posted this question in the roadster section, this is probably a better place...I appologize for posting it inwto places.

I have a 1998 SLK230 with an automatic transmission (722.605). During highway crusing (steady speeds) the RPMs increase (about 200-300 rpms) without the speed increasing. Then suddenly, with a slight thud, they come back down as though the transmission reconnected.
It feels like slighly disengadging the clutch of a manual transmission then popping it...
Has anyone else experienced this, is there a problem, is there a fix? Thanks.

StarPower

Sounds like the torque converter lockup engaging and disengaging.

nine

Tarpower, I assume you are saying thre is a problem here...is there a fix?

nine

Sorry I meant StarPower....

StarPower

Sorry for the lack of detail, I don't have much experience with MB and I don't want to give you wrong information. This post is based on my experiences/knowledge with other cars, and MB may use a different TCC setup.

Probably the simplest possibility is that the brake switch (detects when you press the brake) may be out of adjustment. It'll be a little switch under the brake pedal. You could also have someone check to see if the brake lights come on when you're not pressing the pedal.

If that's not it, then there are several other possibilities. It could be a bad solenoid, a fluid leak inside the transmission, an electrical issue, etc. A reliable shop should be able to determine the source of the problem.

tcesario

need to have a sds hooked up to it and read all adaptation values for transmission clutch fill times ,that usually will tell you were the problem is ,on these cars ,hope this helps ,