2010 E350 CDI Bad Idle when started cold

[Georgi91]

Hi to everyone , Im new to the forum and new to Mercedes. Just recently bought a 2010 E350 Cdi with 69000 miles on the clock and I love it. (Great combo, Blue with cream interior).

What I've noticed is every morning when i start the car cold the rpm goes up and down for 5mins and it feels the car is slightly shaking. Once it gets warm i slightly depress the accelerator and bring the rpm up few times and the car goes to normal and rpm stable. Once it gets to normal temp the car is great. It puts a smile on my face every-time I drive it ! What ive also noticed its a strange smell sometimes around the car when i stop.

Can all of the above be related to the DPF ? Maybe a bad glow plug ? ( Ive just had a B service 2 weeks ago )

If anyone has any suggestions , let me know, but ill be booking a scan soon to check for any error codes.

Thank you all in advance !

 

[RedGull]

Same as mine I think,fuel pump or injector??

 

[Georgi91]

Same as mine I think,fuel pump or injector??

Hi there and thanks for your reply. I Just tried Wynns Injector Cleaner with full tank , but not much happening...... I do hear the fuel pump clicking and doing something when key is in position 2 so you might be right on this one. But why does the problem disappear as soon as i give it a bit of gas when warming up ?

Its really strange .....

 

[RedGull]

That’s my prob! Been to see my indie to ask but by the time I get there all is well!! So they said just drive it until it gets worse then they will sort it, use super diesel, injector cleaner now and then and enjoy,when it gets worse your indie will then be able to find the prob and sort,as you say it’s only for a few mins in the morning

 

[Georgi91]

That’s my prob! Been to see my indie to ask but by the time I get there all is well!! So they said just drive it until it gets worse then they will sort it, use super diesel, injector cleaner now and then and enjoy,when it gets worse your indie will then be able to find the prob and sort,as you say it’s only for a few mins in the morning

Have they checked it for any codes? Ive got a Mercedes Approved indie close to me who serviced my car and i might get them to come and check it when cold in the morning. I do love the car and its depressing when i start it up and behaves like that .....

 

[RedGull]

There won’t be codes if like mine, mine has none so they say it’s perfect, by the time I am there no stutter as warm, don’t bother me much now , had for 6 mths ,will get it in the end, cannot be much

 

[RedGull]

There won’t be codes if like mine, mine has none so they say it’s perfect, by the time I am there no stutter as warm, don’t bother me much now , had for 6 mths ,will get it in the end.

 

[Dodipops]

Glow plugs and or relay?

 

[Smart320]

Don't think glow plugs, they shut off as soon as you start, unless the g/p light is coming on again for a minute after it goes out, this would indicate a problem with the glow plug (s) or controller , in any case they would have no effect once the engine is started and running

 

[Dodipops]

So the glow plugs don’t have an afterglow function, they just shut off as soon as it starts!

Granted the system is pretty reliable to put a light on should there be a fault so likely not to be that just starting at basics when cold start mentioned.

What about temp sensor, does it read realistic when cold?

 

[Georgi91]

Quick update: Just started the car in the afternoon yesterday and it was pretty hot outside and the idle was better then the cold morning ones.

Thanks

 

[RedGull]

Yep same as mine!!

 

[Georgi91]

Yep same as mine!!

Can it be bad battery ? Ive noticed every-time I open and close my window the dash dims its self , but then can the weather affect the battery in any way ?

 

[RedGull]

Would not of thought so, I bet I am not far wrong,

 

[Georgi91]

Would not of thought so, I bet I am not far wrong,

It got me thinking a bad battery would also affect the fuel delivery and the injectors. As you said the fuel pump might be a problem , but then a weak battery would also affect the fuel pump and many other components and as soon as i press the accelerator and bring the revs up everything gets back to normal. Also noticed that sometimes its difficult to start and have to hold the key a bit more than the usual quick key turn. Ill check the battery first before i do anything else. Can someone please confirm if my car has 2 batteries or just one under the bonnet ?

 

[RedGull]

If your has stop start there will be a small one in the boot! motorbike size, normal size under bonnet

 

[RedGull]

Hope you are right!! Give it a charge and let me know please!