Help - Engine not firing after working on it

[Tobes]

Hi,

Wondering if someone can help - I have spent the weekend cleaning the inlet . throttle actuator on my GLA 220d, 2016 with an OM651 engine. However after re-assembly I cant get it to start. The engine cranks but does not fire.

I only took off the inlet pipe and not the whole manifold, so didn't touch the fuel system.

I have Star, and no faults are showing. Tests on the throttle actuator seem fine - moves to the angle commanded to. On the startup test though I am seeing "Ignition OFF / The combustion engine was not started":





Note that the battery was flat after trying to start a few times, and having the ignition on when using Star - so that is I believe why the battery voltage is so low. However sensors seem synced, fuel pressure OK as far as I can tell. I am going to try again after charging the battery as maybe the battery has been too flat since the start of trying, however was OK before starting the work, and I think would have been OK on the first start after reassembling.

Anyone any ideas - especially with the "Ignition OFF/ The combustion engine was not started" message?

Thanks in advance!

 

[optimusprime]

I would fully charge the battery and try again ..if battery is low the ecu will cut all accesories to save information thats stored in it .

 

[ALFAitalia]

Looks like it below minimum cranking speed.....200rpm plus rpm required to fire the injectors and you are showing only 151 rpm......so yes Id charge the battery first. Also, just for technical accuracy there is no throttle in a direct injection diesel. Engine speed in controlled purely fuel pressure and injector duration. That flap is there purely to avoid the thump you get on old style dervs when you close them down and to help create a partial vacuum to assist the flow of gas through the EGR. Some tuning shops remove them completely....not recommended though. Correct name is a shutter valve or anti shudder valve.

 

[Tobes]

Thanks all for you comments - finally got it running!!

I charged the battery overnight, however trying this morning still no luck. Bought some easy start, and also jump leads so I could connect another battery I have. Finally fired a couple of times on what seemed one cylinder when using both batteries and a squirt of easy start. Tried cranking over again a few times, initially seemed to be firing on one cylinder then eventually on couple of cylinders then burst into full life!

Not sure why it was so hard to get going, as I never touched the fuel system. Could have just been some of the soot after cleaning out the intake got into the cylinders preventing it firing properly.

Took for a test drive all is good, and restarts instantly. Truth will tell tomorrow morning, as it could be the glow plugs not working, although no codes and the glow plug light lights then goes out as it should on the dash.

I didn't plug in the Xentry to see what that was doing, but rpm while cranking even with two batteries didn't seem much higher than before. Might plug in Xentry to see if any codes and run the startup test again, just for interest more than anything.

 

[Tobes]

Just to add to this, this was the state of the inlet manifold before I cleaned it out. I was getting charge inlet flap fault codes - p200a21.



Codes all OK now. Not surprised the flaps were getting stuck!