E270-cdi / year 2000 / sudden cutouts

[Woody]

After driving on the motorway at a steady pace for a prolonged period of time and letting go of the gas, the engine dies. The car won't start for 30 minutes. After 30 minutes it will start normally. Happened 25 times in the past year. Multiple service stations are unable to find the problem.

No obvious vacuum in the fuel tank.

My wife hates the car. I want to keep it. My ass is on the line. Help !!

 

[miro]

Are there any error codes ?

Are you talking about Mercedes workshops or some other providers ?

 

[Woody]

Are there any error codes ?

Are you talking about Mercedes workshops or some other providers ?

Strictly Mercedes shops - No error codes - The car is an automatic.

 

[Brian WH]

This sounds like an "overheating problem"? Is there any other signs before or after cut-out, like water temp high etc?

 

[Dieselman]

Start with the crank angle sensor.

 

[Woody]

This sounds like an "overheating problem"? Is there any other signs before or after cut-out, like water temp high etc?

No signs of overheating at all. But it takes a solid 25 to 30 minutes before I´m able to start it again.

 

[Woody]

Start with the crank angle sensor.

Thanks Dieselman,

What is the relation between the crank angle sensor and engine cutouts while decelerating?

 

[Dieselman]

Not sure but the sysptoms seem to indicate this. They are more prone to go on petrol engines, probably due to the extra heat, and fail when hot and the engine is coming to idle.
No codes as there is no indication the engine is turning due to that being the sensor that measures it, just no start until they cool down again.

 

[MBTECHNICIAN]

i have had a few 211s DOING THIS the first thing to check would be the crankangle sensor.you must check the resistance of the sensor when the fault occurs if it is open circuit this is the fault,if it reads approx 1700 ohmns then its ok....
i have also had a oil level/temperture sensor to cause this problem. the only way you can determine if this is a fault is to go to a merc dealer and drive the vehicle whislt checking the actual values of the engine oil temperture(i cant rember the value but i think its around the 95oc MARK)
If the oil temp reaches this then it will shut down the engine management system and will not restart until a suitable temperture is obtained from the sensor.the engine tempture (not coolant temp) is probably ok its just the sensor reading incorrect

NOTE
both faults most of the time do not show up fault codes


hope this helps

 

[bolide]

This reminds me of the cruise control thread where the car would die when on cruise. What was the outcome of that thread?

If a diesel stops and won't restart then surely the fuel feed must be shut off. In the 30 mins that it won't restart is there power at the fuel pump in the tank? Is that pump running? Does the engine turn over when you turn the key? If not it's very obviously electrical/electronic. If it cranks, is there diesel at the injectors? If there isn't it's very obviously fuel system-related

If it cranks and there is diesel at the injectors you need a higher authority to diagnose it...

Nick Froome
www.w124.co.uk

 

[Dieselman]

If it cranks and there is diesel at the injectors you need a higher authority to diagnose it...

What, sort of "Him upstairs"??

 

[Dieselman]

This reminds me of the cruise control thread where the car would die when on cruise. What was the outcome of that thread?

If a diesel stops and won't restart then surely the fuel feed must be shut off. In the 30 mins that it won't restart is there power at the fuel pump in the tank? Is that pump running? Does the engine turn over when you turn the key? If not it's very obviously electrical/electronic. If it cranks, is there diesel at the injectors? If there isn't it's very obviously fuel system-related

If it cranks and there is diesel at the injectors you need a higher authority to diagnose it...

Nick Froome
www.w124.co.uk

Nick
you're thinking of good old fashioned diesels that didn't need electronics to make them work. This is a common rail engine and works just the same as a multipoint petrol injection setup.
There may be plenty of fuel pressure but if there is no signal to tell the ECU the engine is turning then it won't fire the injectors so no go.

If you weren't confused before, you are now!

 

[bolide]

That's exactly what I meant by higher authority...

So the CDis will sit doing nothing till the ECU open the injector? Makes sense in a way as they're common rail and the if the injectors opened under pressure they'd be open all the time

I was going to mention that my knowledge ends with traditional diesels but I obviously don't need to now!

Nick Froome
www.w124.co.uk

 

[Woody]

i have had a few 211s DOING THIS the first thing to check would be the crankangle sensor.you must check the resistance of the sensor when the fault occurs if it is open circuit this is the fault,if it reads approx 1700 ohmns then its ok....
i have also had a oil level/temperture sensor to cause this problem. the only way you can determine if this is a fault is to go to a merc dealer and drive the vehicle whislt checking the actual values of the engine oil temperture(i cant rember the value but i think its around the 95oc MARK)
If the oil temp reaches this then it will shut down the engine management system and will not restart until a suitable temperture is obtained from the sensor.the engine tempture (not coolant temp) is probably ok its just the sensor reading incorrect

NOTE
both faults most of the time do not show up fault codes


hope this helps

Thanks, I will start with the crank angle sensor. Step two, the oil level/temp sensor. I will keep you posted on the outcome. I appreciate your help.