bfnnrgn

Over the last few months my E55 has been having odd power loss problems. I've taken it to the dealership several times and they were unable to find any problem, yet the problem remained. The other day as I was cruising down the freeway when the transmission seemed to disengage. The dash indicator said D, but the car was acting like it was in Nuetral. I could mash the gas, the engine would rev, but nothing would happen. I drifted to the side of the freeway and tried to use the buttons on the wheel and the stick to shift it into 1st or something else but it was stuck in D. After mashing the gas a few times with no luck the car rolled forward a few feet as if the transmission had tried to engage but failed and after a few more tries it was back to 'normal' and I was able to drive it to the dealership. I left it with them and they came back and said they might have to replace the ECU and were running more tests, but they did know they needed to replace the valve body and that they had ordered one.

The question I have is where is the valve body and exactly what is it and what does it do?

Grumpy666

The valve body is in the transmission. When you pull the transmission pan off, it's right there. It essentially controls the functions of the tranny by modulating fluid flow to various shift solenoids, accumulators, etc.

bfnnrgn

Gotcha. Thank you for the reply. They found one in Chicago and they said it was the only one in the states. They're going to try to get it but if they can't then they have to order one from Germany which could take a while.

Jakpro1

Yikes....try to get them to line up a loaner car before you take it in. If they don't reserve one, a lot of guys are pi$$ed when they show up expecting it on dropoff.

When you get the loaner, of course beat the tar out of it in revenge.

Keep us posted. First tranny problem like that I have heard.

bfnnrgn

They got me a loaner, a C230. They were kind of expecting me as two days before I had brought it in for being sluggish from a stop and not downshifting when trying to pass. I explained that the car was acting like it was starting in 3rd gear as it had no pick up to it at all and the exhaust note sounded like a car that was being run in the wrong gear. They looked at the computer codes and transmission codes and found nothing and a short demo drive revealed all was normal and sent me on my way. They said however if it acts up again to bring it straight in and don't shut the car off. Few days later the tranny cuts out and I showed back up and they took it away.

I had been experiencing issues like this for three months but as time progressed they got worse and they weren't able to determine a cause before and to be honest I think they were becoming annoyed that I kept bringing it in only to find nothing wrong. It wasn't until they stopped relying on computer codes so much and I got someone who actually looked at it physically that they found the problem. Hopefully this takes care of it once and for all.

Kar don

yep sounds like a valve body. Like Grumpy says it controls fluid flow to the trans.

SLK55R

I had this problem in both of my CLK430's ... both 98 models. You would have thought they would have fixed this type of problem by now. WTF.

bfnnrgn

Well I got my car back from the dealership the other day. They put in a new valve body and so far so good. I asked the service rep what had happened as the AMG 5 speed was nearly indestructible. The rep said that over the last 2 months she has put in two new valve bodies into cars with the AMG 5 speed. She informed me that there were some issues with them and that Mercedes has quietly came out with a new revision of the valve body to correct some flaws but they weren't on recall.

Although when I dropped it off the lead tech (he was the one diagnosing my car) said there was an airpump recall and asked if I wanted to have it done. I said absolutely not, but when I picked it up I saw on the paper work that they did it anyway.

RJC

How's the power since the airpump campaign's been done?

bfnnrgn

Since it was running poorly before it's kind of hard to say. But butt dyno says it's as stronger than ever. When I got on it after I got it back it actually scared me.