60 days ago I had the TCU replaced because my car was shifting into neutral when I would punch the gas to pass or would not shift out of first. Very dangerous when pulling out to pass in oncoming traffic.
The TCU was $1312.50. total cost was $1881 for parts and $742 for labor.
Car has been fine for 60 days, but now it feels like there is some kind of electronic cutting out. You can feel the car hesitate for just a split second, like a missed heart beat. It doesn't seem to matter what gear I'm in; still has this wierd cutting out. Almost like the car looses all power but only for a mini-second. The tach stays constant and so does the speed, if I'm using cruise control
Yesterday I took a drive with the mechanic and he seemed to think it would only do this at about 60 miles an hour or more and would stop if downshifting into 4th gear. But I've noticed it does this even in 3rd gear at 40 miles an hour. Actually probably will feel this at anyspeed. It's hard to describe the symtoms that's for sure.
When I left the car on Sat at the dealer I explaned the problem best I could. I got a call on Monday morning telling me what I was feeling was probably worn out motor mounts and I was feeling the engine shifting. I was sure that wasn't what I was feeling. Although they did show me that I do need them as the motor will sort of lift up when hitting the gas and breaking at the same time. Engine lifts quite a bit on the driver side.

OK anyway. Car has had no prior issues with tranny until I had the shifting issue two months ago.
The shop is telling me I need a new transmission and will credit me what I've already spent. To me it feels like the transmission is getting a mixed message electronically?? It sort of feels like it wants to shift and then doesn't. Wouldn't this effect the tachometer though?? Oh BTW, there aren't any fault codes coming up when hooked the computer.
Yesterday when they thought it would sort of correct when in 4th gear they said; "just drive in 4th" or drive until it breaks down. But it doesn't feel right and I feel somehow it will damage the car or engine in other ways. Could it be a faulty TCU the one they replaced??
Please help. Anyone had this problem.
Oh I have 70,000 miles on the car.
Thanks, Jack

 

Your car is a W208, so you should post in that forum. This is W209s.

 

Damn, thanks.......

 

I just now read your post of your transmission problem. I have the same issue. When I punch it, it will kick into passing gear and accelerate but will not kick back into high gear. I then get a (clunck) and the car kicks into natural. I have to pull over to stop, put the shifting column into natural and then back to drive in order to drive again. This only happens when I punch it into passing gear. If I gradually increase the speed it is fine.
Have you found a solution?

 

Sounds similar to an issue that I had a while back. I replaced a solenoid and the circuit board. Real easy fix, not much more than a trans fluid change.