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E300 TD cut out while i was driving on the Motorway why ???

5361 Views 35 Replies 7 Participants Last post by  naut1que
hello all i was driving on the motorway/highway @65 MPH
and the car cut out
there were no noises
it has done it twice both on the highway at 65 mph 10 miles (16 Km) into the journey

do you know what the problem could be ?
is this common ?

i cleaned out the MAF sensor and its housing which was blocked with flies
and dirty and now it runs cleanly

but could it be another reason ???
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The MAF will throw a code if it's causing the problem. A failing K40 relay module probably will not, but will stop you cold.
The MAF will throw a code if it's causing the problem. A failing K40 relay module probably will not, but will stop you cold.
thanks is this a common problem
and does it sound like the k40
The K40 module will fail with age. It's very common. I resoldered the connections in mine and it's been fine since (well, since the second time; the first time wasn't sufficient). If you do this, be sure to use a high-wattage iron for the big connections, then resolder all of the small connections to eliminate stress on them (I did not do this on my first, failed attempt).

It's not a very expensive module, or I wouldn't have attempted soldering it.

Another common problem on gassers is the crank position sensor. I don't know if this would be an issue for your turbo 606.
thanks again
if it happens again i will change the k40 module
is that its "ask at the counter name"
Probably. You could also remove the cover from the module box and write down the part number. The K40 is right at the front.
You had

bugs and such in the maf body?where is your air filter?Get a new filter,clean the maf with crc brand maf cleaner and see if that helps.
Doing proper maint at the factory interval is most likely what is needed.
what is the K40? I had the exact same thing happen to me on the highway. Just one time, but hasn't happened again.
It's at the very front of the module box, under the hood.
On the other hand I had leaky fuel lines in the car with 230 k and now the same thing happens on the car with only 185k miles.
Leaky orings allow air to enter the system and it can purge several miles down the road.
It is good idea on cold morning to observe fuel in the clear tubings for bubbles of air.
If they are not clear anymore -it might be good time to replace them.
My 97 E300TD (130000 miles) cut out just before christmas about 500 yards from my house whilst driving. I had no joy leaving the car at the side of the road (level ground) and cracking it (jump leads attached) over the next few days. On each visit, the first time turning the car over, it appeared to be trying to fire but just didn't have enough fuel to do so and then subsequent attempts..... nothing in terms of it even looking like it was going to fire up.
Took out the K40 relay to have a look at it (it was different looking to pictures I've seen on the web) but didn't see anything obvious connection wise. Reconnected and tried tapping it with a screw driver whilst cranking but still didn't start. Eventually got it towed back to the house (parked on a downhill slope) and the next day went out and turned it over. First time it didn't start but showed signs of firing like the other occasions. Tried second time and it started but was very lumpy for what seemed like a minute then it smoothed out and I have had no problems since

I have twice had problems recently where it wouldn't start and my local mechanic chequed the fuel lines for leaks but everything is as dry as ghandi's flip flop and he didn't notive any bubbles so he didn't change them.

My thoughts after reading some of the posts is that my problems are the fuel lines and that they are leaking air in rather than leaking fuel out and this is causing my intermittant problems. I am assuming that my engine cut out whilst driving because a certain ammount of diesel was in the system and available to the injectors before the air blockage cut off the fuel supply and it was only when I got the vehicle on a downhill slope that gravity played it's part in filling the fuel lines again. Tank was just on a quarter full btw. Is there anything else I should be thinking of? It just doesn't sound electrical. Is there anything related to the behaviour of the shut off valve which might be worth looking at?
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Oh yes CR ...should have mentioned that my mechanic serviced the car (all filters) when he had it and was checking for fuel leaks. Thanks
Did the mechanic check for air leaks into the fuel lines?
The fuel lines are clear tubings for a reason.
He told me he did K1, but they are discoloured pretty badly so they are not that easy to check IMO.

How easy is it to spot air getting into the system? Is it continuous bubbles flowing past on the air lines? I tried to check using a torch on the pipes either side of the fuel filter and couldn't see anything obvious
I did the job on 2 cars already. If the tubings are discolored that would be indication that the seats are aged as well. Set of 5 or 6 tubings cost in the range of $70 from Internet vendors. Besides orings on clear tubing there is one more behind the shut off valve. This one failing will not show air bubbles in clear tubings.
With my present practice replacing them all is like 15 minutes job. Wash the area well with water before the job.
Ask moderators why that constantly coming topic is not is stickies ;)
Parts including O ring behind shut off valve ordered up. £44 in total. Thanks for your assistance guys. Spoke to my mechanic and he's still sceptical about this being a fix. Can't understand why it cut out whilst I was driving. Said that once you get them started a little bit of air in the fuel lines is normal enough for most cars and thought it wouldn't have cut out once started due to an air leak. We'll see soon enough. Parts should be in by Friday so I'll post again next week when I get the work done
Got the lines fitted bar a couple of them (dealer supplied the wrong parts) and the SOV O ring. Mechanic also fitted a priming bulb to the system. He still doesn't think it's my problem, but we'll see how it goes. I'll keep you all posted over the coming months.
Priming bulb?
Your mechanic is trying to outsmart Mercedes engineers.
This can't be good.

Would you mind elaborating Kaj? It's just some people may not have a clue what you mean (not me of course :rolleyes:).
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