New car 2007 320 cdi auto issues

[Grand Tourer]

Hi all, I'm new here.

I've recently bought a 2007 E 320 cdi auto, estate, FMBSH, second hand off a seller who I thought looked trustworthy. I also thought that being a Merc the 100,000 miles wouldn't be a problem.

Unfortunately, when the car is cold the auto gearbox is very jerky when coming to standstill, it gives you a very heavy 'thud' in the back. The gearbox is fine at other times and once warmed up.

It also doesn't start on first turn of the key, wanting to turn sometimes for several seconds when cold, which is not what I would expect of a modern car.

And, yes I know they're heavy cars, but I've been getting 28mpg on a 12m daily commute most of which is dual carriageway. And even on a run to Birmingham and back, all of which was 65/70mph steady moving traffic, I still only got 36mpg (tank full to tank full). I don't drive with a heavy foot.

It's booked at a specialist next week for diagnosis, but does anyone have any suggestions?

Jeremy

 

[Dieselman]

Change the gearbox fluid, check the injector leak off rate, add a dose of injector cleaner.

None of the above sounds alarming.

 

[Grand Tourer]

Change the gearbox fluid, check the injector leak off rate, add a dose of injector cleaner.

None of the above sounds alarming.

Thanks that's reassuring, but I guess I'm always nervy when Auto gearboxes are concerned. Is it possible that one thing, such as the choke, could be causing all 3 issues?

 

[Zu11y]

I had a similar issue on my clk320 cdi, changed the fluid and filter and the difference was amazing. does the service history show any fluid changes, if not at 100k it is well due for one.

 

[Dieselman]

It's a diesel, so no choke as such. Does it rev a little higher when idling and cold?

Modern diesels have a lower compression ratio than older ones, so do need the glowplugs for an easy start. Are you waiting for the light to go out?

 

[Grand Tourer]

It's a diesel, so no choke as such. Does it rev a little higher when idling and cold?

Modern diesels have a lower compression ratio than older ones, so do need the glowplugs for an easy start. Are you waiting for the light to go out?

yes the glow plug light is taking a second or so to go out and then I turn the key.

 

[markheaney2]

the shunting of the gearbox when cold is more or less standard i have 2 2007 cars they are both the same even after oil changes on the box when warm absolutely perfect

 

[BlackC55]

You may need the adaptations re-set. This involves driving the car with the Star attached while going through a correction program.

 

[Grand Tourer]

You may need the adaptations re-set. This involves driving the car with the Star attached while going through a correction program.

I'm really sorry to appear thick but i didn't understand a word of that!

Adaptations? Star? Correction?

 

[Grand Tourer]

the shunting of the gearbox when cold is more or less standard i have 2 2007 cars they are both the same even after oil changes on the box when warm absolutely perfect

Is this really the case? I've driven big diesel cars for the past 10 years, Toyota, Vauxhall, Rover, BMW, Volvo and 3 different Jaguar S Type 2.7D. None of them ever 'shunted' like this except for one of the Jaguars. I'm sure no major car manufacturers ever make a car that comes out of the factory doing that.

 

[BlackC55]

I'm really sorry to appear thick but i didn't understand a word of that! Adaptations? Star? Correction?

Adaption is the data the gearbox holds inside it's control unit. (Computer) it learns you driving style to optimise the drivers comfort.

A Star is the MB diagnostic equipment.

A star is used by mb dealers and specialists like me to help diagnose faults.

 

[mbenz1]

Regarding the starting problems on cold start, it could possibly be due to the glow plug module thats not functioning correctly. Its a very common problem in the V6 CDI diesel and you can even search this forum to see people complaining about cold start problem in the V6 diesel. Or it can also be the glow plugs. The star diagnostic check should indicate if any problems are existing in the module or plugs but sometimes the star check does not show up any faults... The module is not very expensive to buy and get fitted in my opinion

 

[Grand Tourer]

Thanks guys, I'm feeling a lot less anxious about it now. Just wish I'd bought a low mileage vehicle though

 

[Dieselman]

Thanks guys, I'm feeling a lot less anxious about it now. Just wish I'd bought a low mileage vehicle though

For more money...

Don't worry, it will be fine.

 

[panason1c]

Thanks guys, I'm feeling a lot less anxious about it now. Just wish I'd bought a low mileage vehicle though

If it's any consolation....... MB's find all sorts of ways to lighten your wallet at all mileages.

 

[machineheadrock]

If it's any consolation....... MB's find all sorts of ways to lighten your wallet at all mileages.

Nooooooooooooooooooooooo

Dont say its true! lol

 

[boblydon]

you will soon have the joys of the inlet port motor and inlet manifolds to look forward to.....now that will lighten your wallet lol lol.

still great cars though !!

bob

 

[stonebasher]

Hi I have a 2007 MB estate W211 diesel brought 18 months ago from MB retailer genuine 45.000 miles now done 71.000 miles I have got problems at first wheel vibration balancing did not cure had 4 new alloys, which has cured it but it has developed suspension noise as though some thing broke or loose, ( I guess broken springs)? On a trip to France last august I had to top up engine oil, when I arrived at destination I noticed oil dripping, checked and realised the oil cap not on correctly. On the journey back gear box will not change remained in what seemed 3 gear, then after slowing down it would not change up in the gears, it corrects itself if I stop switch off engine then restart all is then OK this has continually been like that up to yesterday when it will not correct itself, so called out AA it is now in Garage gear box repair shop, I am told the computer read out is saying Auto gear box sensor, and gear change valves stuck?
A friend who had a similar problem with his CLS petrol cured his problem by obtaining info off of web, about resetting the computer this has not worked on mine, any ideas on what is wrong
Thanks