Hot start issues - S211 E320 CDI (om648)

[Rawhide]

Hi all. I've got a pair of 2004 E320 CDI estate cars. One is a dog of a car (my wifes) but low mileage (relatively speaking) with 102k on the clock. It's had a map at some point in its prior life.

I also bought a 2004 E320 estate which was intended as a parts car to fix up the dog but it ended up being a really clean car so its now my daily driver. It has 164k on the clock.

I've replaced the fuel filters on both cars, also replaced the injector seals on my 164k car. They are all nice and tights.

My wifes car does not need injector seals but is starting to not want to hot start. Cold starting is fine and the car cranks ok. Both cars have had some rodent damage. I had to replace a fuel line in my wifes car after a mouse ate clean through a hose leaving her stranded. I used high quality fuel line rather than a MB hose. Mostly due to availability but also price as she was stranded. I noticed her fuel hoses are starting to perish so I plan to replace them all with the hose I bought.

My car has had a hot start problem twice ever. Her car has done this now three times in the last week. Once with myself driving. The car was hot and sat for 5 mins. It would crank and almost fire but then die. 5 mins later it starts and idles just fine.

No discernible blue smoke from either cars. They both idle fine. My car *might* be down on power but it's hard to tell as my wifes car is mapped. My car is a lot smoother and does make full boost.

I do have star, but I'm far from a STAR expert in knowing what to look for. I need to scan again but I don't remember any codes of use when I last scanned the car. No CEL either on the cars.

I would welcome troubleshooting advice. I'm thinking;

1) Injectors 'leaking' as suggested by the AA man attending my wifes breakdown
2) O'ring issue in the fuel system.
3) Air leak elsewhere in the fuel system
4) Poor fuel quality (usually Tesco but a 'high transit' station)
5) ?

I could take this to a pro but both cars are doing this so I'd be keen to try it myself.

I have bought a can of 'BG 245 Premium Diesel Fuel System Cleaner' for my wife car which can't do any harm.

 

[ajlsl600]

Crank sensor, playing up when car hot? If u have star look fault codes save then delete them start car cold see what shows up. If nowt let car get hot. Try again.
Fuel press dropping when parked hot.
If I could not see any cause I would start at first point myself.

 

[Rawhide]

Thanks ajsl600. I bought a crank sensor the other day (as I was broken down next to a parts store) but I didn't want to change it unless I knew what to look for. I also thought perhaps incorrectly that a crank sensor would result in cold starting problems as well.

 

[mioba]

sounds like a vacuum leak somewhere

 

[brandwooddixon]

As a crank sensor degrades it will generally cause the engine to stop when its hot, hence the engine will need to cool before it will restart. Usually though the engine will stop again. I believe that you can test it by placing it in hot water and measuring its resistance - search this site, its mentioned somewhere, I think by Malcolm (Television).
I've known cars not start with a camshaft sensor fault.
I don't think that either will trigger a warning light on the dash.
With STAR you should be able to read off the codes, in fact you may be horrified by how many codes have been recorded that don't trigger the EML!

 

[Rawhide]

Hi - as an update to this topic as you guys were so helpful in assisting. When I ran the car on STAR the engine did not have any current faults. The was a stored code for the Camshaft hall sensor. As I had a crankshaft sensor with me I had planned to swap it anyway as its not expensive but my hands were too big to get to the bolts. As such I swapped the crankshaft sensor for the Camshaft sensor at the parts store and fitted that which was simple.

My wife has not had any more issues so far but I can't be sure the issue has gone for sure, only time will tell.

I expect it's unrelated but I had to swapout the shifter on her car as it seemed the main wiring harness was not seating well. This was causing the car to be stuck in park, not start and when shifted using the overide it would not shift up.

Now the unit is swapped it's shifting just fine. I expect this was just a co-incidence with these old cars.