2010 E250 om651 Turns, but won't catch after repair

[phiof]

Hi all,

I've pretty recently got a 2010 e250 (s212 diesel), it's my first time outside the VW/AUDI space.

I had a leak from my rocker cover and also fuel filter housing so thought I'd give it a go and replace them.

Yesterday I replaced the fuel filter housing, which was a bit tedious as I had to remove the EGR Cooler so that I could get easier access to the filter.

All seemed to go smoothly, and as I got part way through trying to get started on my rocker cover gasket replacement (I removed c1&2 fuel pipe and also the return lines) I realised the rocker cover bolts were all pretty loose after which I just torqued them all up and plugged everything back in.

Then I had a chudder upon cranking the engine which was quite pronounced and after running it for a while i got code P0263 (Cylinder 1 contribution/balance).

This morning it was still the same after which I removed the fuel pipe and return and when I put them both back in and cleared the code, now my engine will only crank and not turn over.
Fuel pump works as I can definitely hear it starting when I turn ignition on!

Unsure what to do, all seems ok, all sensors are plugged in and everything is as it was previously. Maybe someone has been in a similar situation before?

Thanks for your time,
Joachim

Update: I somehow managed to get it to start up again - has to crank a good few times. But running rough, shaking super abnormally

 

[Tonygw]

I'm no expert but it sounds like an airlock in the fuel system, the fuel filter needs to be primed by turning the ignition on/off about 20 times.

When you removed the fuel pipe and return, did fuel come out?

 

[phiof]

I'm no expert but it sounds like an airlock in the fuel system, the fuel filter needs to be primed by turning the ignition on/off about 20 times.

When you removed the fuel pipe and return, did fuel come out?

Thanks for your reply, I’ll give this a try.

I replaced the fuel filter as it was needing replacing anyways, but i can definitely see fuel coming out of those hoses.

It seems to be around the fuel rail that it’s not getting fuel - initially it was just c1 struggling for fuel but now after fuel filter was replaced, nothing seems to work as it won’t catch at all.

I’ll check back once I’ve primed a good few times!

 

[mersum1es]

Piezo injectors get air lock easily if they are laying on table ... SDS has bleeding procedure for them, otherwise it is nerve breaking high revving until it resolves... BUT if it is some other thing, that will definitely kill your engine so won't recommend it.

 

[phiof]

Piezo injectors get air lock easily if they are laying on table ... SDS has bleeding procedure for them, otherwise it is nerve breaking high revving until it resolves... BUT if it is some other thing, that will definitely kill your engine so won't recommend it.

Hm, I never took the injectors out, only the feed and return lines, though this could have somehow got air trapped in there.

 

[mersum1es]

Hm, I never took the injectors out, only the feed and return lines, though this could have somehow got air trapped in there.

Ok it should not. See that injector connectors are tightly in, check no pins are withdrawn inside them. Check all fuel lines are tight in place.

 

[phiof]

Piezo injectors get air lock easily if they are laying on table ... SDS has bleeding procedure for them, otherwise it is nerve breaking high revving until it resolves... BUT if it is some other thing, that will definitely kill your engine so won't recommend it.

Alright, I did the recommended 20 primes, gave it a good 10 more just to make sure, doing through the full cycle.

Also took everything apart again and put it back together making sure nothings leaking and all seems ok

Still nothing catching, but does still crank

When I prime, I do hear a small hissing sound coming from the engine bay, though I don’t recall hearing this before, I never really paid attention so it could have been - there doesn’t seem to be any fluid on the floor below it

Any idea what ideal readings should be for fuel rail etc? Not sure whether it’s accurate but when monitoring fuel rail pressure I was getting a jittery reading of 0-1bar fluctuating super speradically