Hot Start issue (M111.960)
 

My W124 E220(M111.960) has trouble starting when hot.

Symptoms
1) When car is hot/warn I need to crank longer.
2) When car starts it shows symptoms of miss-fire, feels like only couple of cylinders have fired, Pressing accelerator fixes the issue.
3) I don't see this issue when Re-starting interval is short ( < 1 min).

Diagnosis
1) No error codes
2) Fuel pump starts humming when fuel level is low ( < reserve), otherwise operates normally.

Solution ?
From what i could gather from previous posts is, it could be
1) Fuel pump ?
2) Accumulator ?
3) Injectors ?

• How do I check which injectors are bad?
• Will cleaning do ?
• Is replacing injectors DIY?
• What other parts do I need if I have to replace injectors?

Thank you

bump!

Fuel pressur bleed-off is a good possibility. The fuel pressure regulator is designed to hold fuel pressure in the rail for at least 24hrs.

If you can attach a fuel pressure gauge and check for bleed off.

I'm not following you here Doc. If the OP's complaint was of cold hard starts I could understand this better (i.e., pressure leaking away overnight). But since cold hard starts apparently aren't a problem, the notion of fuel pressure loss as the cause puzzles me. Symptoms seem more like leaky injectors flooding the engine after it's been running and then sitting awhile, but still hot. What am I missing?

Ok, will check that, would it bleed into the vacuum line?

Edit: Got this http://forum.mercedes-benz-clubs.com/viewtopic.php?t=20579&sid=d0e649178dccaf14e83c272c4fbb73c4, but I still have same doubt as 'Cal Learner'.

AND, Or back to the tank.

I have the same issue, 90% of the time when cranking cold, it fires up right away... seems that only hot starts are the issue. warm starts are very likely to crank for 5 - 10 secs with holding my foot on the gas and it slowly caughs faster and faster till it finally starts. I did an alldata bulletin search on it and found this... [IMG]file:///C:/Users/James/Desktop/83508998.gif[/IMG]

My 300E does it too.....cold starts are pretty quick (less than 2 seconds of crank time)....but randomly it has a hard time when hot and sitting for more than 15 minutes when re-started. Prompt re-starts hot are no issue (within 10 mins).....sometimes I'll crank 5-6 seconds, no go, and will try again, then it starts right up....some times it will run with a lope at like 200rpm for 3-5 seconds, then come up to speed normally and run fine. Strange indeed. It has never "failed to start" though, it always goes by the second try if necessary....and once started it has no issues at all.

My E220's symptoms are exactly same as pawoSD's 300E, starts on the second try + sometimes 200rpm issue (mostly one or two cylinders don't fire).

I have postponed it for now, but plan to check fuel pressure first when I start diagnosis.

Failure to start after Engine Wash
 

My MB with an M 111.960 E220 Engine wont start after the e4ngine was washed. what could be the problem?