V6 CDI/7G hesitation

[developer]

And I could give up the camping trips and just kip in it, ideal!!!

And go beaver hunting .

 

[rascalmaster]

Bang on topic RM,

This is my beef with the kickdown - it hesitates, which is annoying.

... like a shrinking violet
Something that did help the gearbox become smoother (apart from the ATF change)... was me changing the air filters
On inspecting the ones I replaced; they were really badly clogged!
I've had the car a year during which I had a new turbo under warranty, and as part of the diagnostics process leading to the new turbo- the air filters were replaced... or were they?

Not that I'm the suspicious sort... but the way I see it; filthy filters is probably old filters

 

[developer]

... like a shrinking violet
Something that did help the gearbox become smoother (apart from the ATF change)... was me changing the air filters
On inspecting the ones I replaced; they were really badly clogged!
I've had the car a year during which I had a new turbo under warranty, and as part of the diagnostics process leading o the new turbo- the air filters were replaced... or were they?

Not that I'm the suspicious sort... but the way I see it; filthy filters is probably old filters

I recall our air filter discussions on a previous thread.

What was wrong with the turbo - did it show as a fault on the display?

 

[C240Sport97]

There is a lot that is not on the MB UK price list that you can still factory order, they just don't put it on there to discourage people from ordering it. As long as they are putting the 5g in high end cars you will still be able to spec it in any other car as a direct factory order (for a price of course) the reason is the 5g box will handle 796lb/ft torque whereas the 7g will only handle 542lb/ft to me that says it all why the 5g is better than the 7g.

which high end cars would that be?

not a 4 pot C class or a 4 pot E class surely?

 

[rascalmaster]

I recall our air filter discussions on a previous thread.

What was wrong with the turbo - did it show as a fault on the display?

Soon after I got the car approved used, I noticed an intermittent fault where on rapid acceleration the car would sometimes lurch a few times as if hunting for the right gear... before accelerating as if nothing had happened...

mercedes tried fiddling with the gear box software, but the fault still came up when I got the car back, and recurred with greater frequency.

They had it in again and told me the turbo had a manufacturing defect whereby because it wasn't spooling up properly; the sensors were getting confused and initiating gear changes. All a bit hokey pokey sounding, but a new turbo later all was cured.

I do wonder if my new turbo is set up properly though ( correct boost pressure etc) as I do'nt really know if it's working, lol
But they do say the turbos on these are quite discrete... and my car pulls from standstill to sillyness without any fuss.

 

[timskemp]

and my car pulls from standstill to sillyness without any fuss.

I like that!

 

[mobeyone]

Don't know if anyone else has noticed this but I get a far smoother and quicker pick up by not using kickdown? It's like kickdown just confuses the car and gearbox but when I floor it the power is there and the gear changes are far smoother?

 

[flango]

which high end cars would that be?

not a 4 pot C class or a 4 pot E class surely?

Mercedes dealers in Germany say that as long as MB are producing 5g boxes for such cars as chrysler 300, dodge charger, jeep grand cherokee, Chrysler cross fire , MB S65, S600 SLR then you can (for a cost ) spec the 5g box in any MB car.

 

[C240Sport97]

Mercedes dealers in Germany say that as long as MB are producing 5g boxes for such cars as chrysler 300, dodge charger, jeep grand cherokee, Chrysler cross fire , MB S65, S600 SLR then you can (for a cost ) spec the 5g box in any MB car.

I bet a UK dealer won't do that for you

 

[rascalmaster]

don't know if anyone else has noticed this but i get a far smoother and quicker pick up by not using kickdown? It's like kickdown just confuses the car and gearbox but when i floor it the power is there and the gear changes are far smoother?

+1

 

[flango]

I bet a UK dealer won't do that for you

I bet you are correct, such is my disdain of UK MB dealers if I do replace the Volvo with an MB it will definitely be ordered from a German dealer. They appear to be able to offer things UK dealers simply can't or won't. They are much more amenable to you speccing the car exactly as you want it.

Strangely enough with BMW ban it's the other way around UK dealers offer options the German dealers don't or won't match, bizarre

 

[st4]

I bet you are correct, such is my disdain of UK MB dealers if I do replace the Volvo with an MB it will definitely be ordered from a German dealer. They appear to be able to offer things UK dealers simply can't or won't. They are much more amenable to you speccing the car exactly as you want it.

Strangely enough with BMW ban it's the other way around UK dealers offer options the German dealers don't or won't match, bizarre

535d with Limited Slip Diff. Yes please.

Would an MB dealer be able to arrange LSDs from C63cs etc to be fitted to this C350cdi 5g with half leather seats I want. That would be some car!!!

 

[st13phil]

the reason is the 5g box will handle 796lb/ft torque whereas the 7g will only handle 542lb/ft to me that says it all why the 5g is better than the 7g.

7g-Plus 'box seems to have fixed that. Two versions with max torque of 700Nm (516lb.ft) and 1000Nm (738lb.ft).

In our house we have an SLK350 with a 7G 'box and an E350CDI with a 7G-Plus 'box. While I can make no comment on longevity, the box in the SLK is infinitely better to drive than the 5-speed 'box was in my W204. The 7G-Plus is even better.

 

[alibally]

Was the engine software updated as well as the gearbox as they should be done together. If the air filters are replaced the engine ecu should also be reset via the star machine. This makes a difference. Resetting the drift compensation for the maf can also help.

 

[crockers]

So you could order an C350Cdi with 5g. Oh good god, my dream car is out there.

Until you come to sell it..... then it will be a P.I.T.A. as no-one will want it.

 

[Beardz]

Was the engine software updated as well as the gearbox as they should be done together. If the air filters are replaced the engine ecu should also be reset via the star machine. This makes a difference. Resetting the drift compensation for the maf can also help.

Last year my E320 needed a "major service" and the air filters etc were changed at that time. I used an indie that didn't have a star machine but had software that could read codes etc.

I wouldn't have thought that anything would have been reset at that time?

Also when i had the atf changed (which i found hadn't been changed in 110k miles!) i don't think i had the box reset or the software updated so would this cause the issues i have mentioned in my previous posts?

The indie i went to for the atf does have a star machine, but would he have done the above as part of the process?

 

[rascalmaster]

Last year my E320 needed a "major service" and the air filters etc were changed at that time. I used an indie that didn't have a star machine but had software that could read codes etc.

I wouldn't have thought that anything would have been reset at that time?

Also when i had the atf changed (which i found hadn't been changed in 110k miles!) i don't think i had the box reset or the software updated so would this cause the issues i have mentioned in my previous posts?

The indie i went to for the atf does have a star machine, but would he have done the above as part of the process?

"I wouldn't have thought that anything would have been reset at that time?"
- i doubt it. star settings post air filter change while desirable, are not imperative.

"The indie i went to for the atf does have a star machine, but would he have done the above as part of the process?"
- doubt it.

 

[alexis.jones]

Will this cure the problem. I have heard a little on it but seems good
eBay - The UK's Online Marketplace

 

[rascalmaster]

Will this cure the problem. I have heard a little on it but seems good
eBay - The UK's Online Marketplace

Sprint boosters have been discussed at some length on this forum...
Some guys swear by them... others point out that all they do is fool the car into thinking you've pressed your accelerator further than you actually have.

 

[Beardz]

"I wouldn't have thought that anything would have been reset at that time?"
- i doubt it. star settings post air filter change while desirable, are not imperative.

"The indie i went to for the atf does have a star machine, but would he have done the above as part of the process?"
- doubt it.

Would you recommend I get the box reset and have the software updated? Is this likely to make changes smoother and less prone to holding onto gears up to 3500rpm when I am not putting my foot flat to the floor?
I am finding my gear changes to be really erratic just lately and a car like this just shouldn't behave this badly