CLK 320 W208 won't start

[David Wilkins]

Hi All,

Can anyone advise where to begin? The car ran ok this morning - was parked for an hour and now the starter won't engage. There are no error messages on the dashboard.

Wife reports a whirring noise from the front - which I think will be the fuel pump (yes it's got half tank of juice) but I can't tell from the office here whether its the normal fual pump noise or not (a very gentle whirring that could not be heard once the engine starts).

Thanks,
David.

 

[television]

This is hard to say, Is the dash lightinmg up in the normal way,,can you hear a click under the bonnet when the key is turned to start

 

[Aussie Nick]

Sounds like a dead battery.

 

[David Wilkins]

Thanks for the suggestions - the dash warning lights come up as usual when the key is moved to the start position. The last position where the starter normally engages appears to not be functioning - as the interior lights don't dim at all as the key is turned (had Wife leave drivers door open). It is possible the battery is dead-ish - it's a very big one but is 3 years old. Thing is, the car started this morning in 5 deg, and now the starter wont engage with a warm motor and 10 deg. air temp. Hmmm

 

[television]

The only way hat this can be solved I think is to put a voltmeter onto the small terminal on the starter motor and see if 12v is present when the key is turned to the start.


Sadly to get to this you have to remove the nearside front wheel liner

 

[bigasotonuk]

Hi,
Would,nt a low battery on this model be indicated in the dash display?

 

[BlackC55]

Hi,
Would,nt a low battery on this model be indicated in the dash display?

Nope!!!

How are your seats doing?

 

[FELLOW]

Crank shaft sensor

If the engine is turning over but not engaging, the battery is good and there is juice in the tank with no error message could just be the crank shaft censor.
If you have had a MB service in the last year call out Mobiliolife who can run a diagnostic and change simple parts under the free breakdown cover.

Good luck!

 

[television]

If the engine is turning over but not engaging, the battery is good and there is juice in the tank with no error message could just be the crank shaft censor.
If you have had a MB service in the last year call out Mobiliolife who can run a diagnostic and change simple parts under the free breakdown cover.

Good luck!

No it cant be that the engine is not cranking

 

[David Wilkins]

Hi - thanks for the helpful suggestiions !

While I was still at work Wife called out AA (one must go shopping ...) and the guy jump started it - effectively pronouncing the battery dead. I dropped by MB on the way home, bought a new one and installed it. Fixed radio and thought all was well. Motor now starts - but runs roughly & wouldn't accelerate properly for a couple of miles. It settled and seems to be running ok but the engine warning light has come on and does not reset. No malfunctions show on dash, plenty of water, oil and fanbelt.

Once again - your thoughts & suggestions appreciated.

Cheers,
David.

 

[television]

Hi - thanks for the helpful suggestiions !

While I was still at work Wife called out AA (one must go shopping ...) and the guy jump started it - effectively pronouncing the battery dead. I dropped by MB on the way home, bought a new one and installed it. Fixed radio and thought all was well. Motor now starts - but runs roughly & wouldn't accelerate properly for a couple of miles. It settled and seems to be running ok but the engine warning light has come on and does not reset. No malfunctions show on dash, plenty of water, oil and fanbelt.

Once again - your thoughts & suggestions appreciated.

Cheers,
David.

Yes this has happened a few times when a new battery is fitted. it will be the MAF packed up.

You can confirm this by unplugging it and going for a test run.
The car may run a little on the rough side, but the power will be back to normal.

When this happens the O2 sensor tries to compensate by changing the fuel / air ratio,

It may need STAR to turn the light out, but it may, and they do sometimes go out on there own

 

[television]

If you unplug and its OK buy one from a Bosch service center as they are £100 cheaper than from MB

 

[David Wilkins]

Thanks Malcolm.

I scanned Euro Car Parts and they have 2 types for this w208 365 112 940 ... one from Bosch at £172 and the other from PWM at £50 ... big price difference ! I'd prefer the Bosch but it is one heck of a price jump. Do you think they are worth that?

Cheers,
David.

 

[television]

Thanks Malcolm.

I scanned Euro Car Parts and they have 2 types for this w208 365 112 940 ... one from Bosch at £172 and the other from PWM at £50 ... big price difference ! I'd prefer the Bosch but it is one heck of a price jump. Do you think they are worth that?

Cheers,
David.

Thats a hard question, how long is the guarantee on the PWM, for all ther is in them they are not worth more than £5

They are sold on Ebay, but make sure they are Bosch from there.

Many people have not had much luck with the cheaper versions