New Mercedes Woes

[pompei]

Following the Saab's write off, I bought a new* (OK 11 years old) MB 320 CLS.  It's the 3.5 V6 diesel auto... and it's very nice. Only drawback is that there is an intermittent kickdown problem where, basically, it doesn't kickdown and nothing happens.

 

I've booked it into the local MB specialist for next week but the guy I spoke to said it could be the engine or gearbox.  I was rather hoping it could just be a kickdown switch.  If I flick it into semi auto, it changes up and down without problem.

 

Any thoughts, O wise readers?  

[Wingz123]

Will be a sensor on the box from my experience having had 320cdi and 220cdi’s e class’ - you will find them on ebay described as “just needs the gearbox fluid changing”......nah not in my experience. From memory there are three sensors on that gearbox. Plugging in and scanning will help to diagnose which one...

 

Have you had it plugged in yet? I imagine also that you average run of the mill obd readers will not be able to delve into the gearbox module and you would need someone with a copy of star to scan it properly....

 

Benefit of star also being that a star wireless module can be plugged into the obd port, the tablet he then has which brings up the results he can sit in the passenger seat whilst you take it for a blap and read live readouts from the sensors....

 

Your MB specialist will have this...

 

Lastly, there is a guy on the MB owners club forum (I am on it for my Sprinter) and he is an admin guy there and responds to literally every post. Very knowledgable and has a huge libary of exploded diagrams and how-to’s so worth joining over there too!

[Wingz123]

Alexanderfoti and miffy are the members to approach on there...

 

Miffy more for diesel q’s...

[New POD]

I know nothing about mercs, but today was the first day I ever drove one. Out of my mates workshop and into the communal indoor area. 

 

Took a photo next the the offending omega which was upsetting me last Friday with gearbox issues. I added a little Red Liqueur and am hoping that it's not something bad.  Hasn't done it since Friday. 

 

[stuboy]

I'd rather have the Omega. Looks like the premium vehicle them both sat there.

oh yeah an  mv6 

[Guest Hooli]

I'd rather have the Omega. Looks like the premium vehicle them both sat there.

 

It really does doesn't it?

[Wingz123]

That omega looking like that in 2.2dti....would be awwwwwwwwwesommmme....yes pleeease!!

[NorfolkNWeigh]

I'm a big fan of the 3.0 V6 diesel and have done not far off a million miles in them , currently in an ML. The only gearbox problem I had was on a 5 speed in a Chrysler 300 , which 'lost' 3 rd.

 

I had the fluid changed in all of them every 60/70,000 and they always get better afterwards( maybe psychological).

 

I had the gearbox ecu fail in a W212 e250 cdi which uses the same 7 speed box- that was a Grand , including filter and fluid( the ecu sits in the sump) But the symptoms were nothing like yours, it just wouldn't restart when warm)

 

Can't see it being an engine fault , more likely the 'valve block ' in the box, which can be repaired these days.

If it's intermittent , I'd just live with it until something definite makes itself apparent. Could be years.

[Peter C]

I’ve had two Mercs with 7G transmissions.

 

The first, circa five years ago, was a brand new W204 CDi 220 Coupe. That gearbox didn’t have a clue what gear it should be in, kepr going up and down gears for no reason and it would flare as the car was coming to a standstill.

 

Last year I bought a 2007 CLS 320 CDi, with 57k miles and FSH. The gear changes were rough and a £200 oil change didn’t help.

 

I hate the 7G ‘box with a passion.

 

Good luck getting yours sorted.

[Talbot]

I'd rather have the Omega. Looks like the premium vehicle them both sat there.

The colour helps, as the bland Germanic silver on the Merc makes it look very boring. Which it is. I'd have the OhMeeGar too, and having driven both models, the O is a lot more involving and interesting to drive.

 

Although I've never owned an Omega, and I'm on my second W210. Because OM606. One of those in an Omega would be both brilliant, and waaaay better than the BMW 2.5td the early models had.

[Schaefft]

I’ve had two Mercs with 7G transmissions.

 

The first, circa five years ago, was a brand new W204 CDi 220 Coupe. That gearbox didn’t have a clue what gear it should be in, kepr going up and down gears for no reason and it would flare as the car was coming to a standstill.

 

Last year I bought a 2007 CLS 320 CDi, with 57k miles and FSH. The gear changes were rough and a £200 oil change didn’t help.

 

I hate the 7G ‘box with a passion.

 

Good luck getting yours sorted.

I think the early 7g-tronic is generally seen to be garbage, and I'd personally try to avoid it if possible. The old 5-speed auto is supposed to be bullet proof if serviced once in a while. I'm not sure how long it took Mercedes to fix the thing, I'm sure they managed to get it right eventually. But knowing that one of my potential future purchases only came with the 7-speed in it, I'm hoping that they got their shit together fast and the later versions are much improved.

[Talbot]

I think the early 7g-tronic is generally seen to be garbage, and I'd personally try to avoid it if possible. The old 5-speed auto is supposed to be bullet proof if serviced once in a while.

The fact that the uber-powerful top-end E and S class models kept the 5g-tronic box well after the lesser models had moved to the 7g-tronic speaks volumes about how near-indestructable the 5g box is. Apart from conductor plates of course, which it will split for a laugh and are a bare minimum £200 outlay even if you do absolutely everything yourself.

 

Also, 5g-tronics do not have lock-up, which is a bit pants.