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Discussion Starter #1
Hello guys!
I have a 190D (european model) equipped with the OM601 and after cold start it will misfire. I changed the glow plugs a week ago and I also checked them today with multimeter and they still work perfectly. Good resistance and all of the get electricity.
During cold start I always wait out untill I hear the GP relay click (around 30 seconds). I'm not starting based on the glow light on the dashboard.
The car starts very easily and all cylinders are working nicely for about 5 seconds but then some cylinder starts failing to ignite and the whole car shakes. The only way to keep the engine alive is if I apply a bit of throttle to raise the rpms to around 1300-1500. It still misfires but at least it wont shut down.
The engine starts to smooth out as it gets up to temperature and in about 1-2 minutes of driving (based on outside temperature) the misfire is gone.

It feels like the reason it's good right after start is that the glow plugs are still hot and help ignition and as they cool down the trouble starts.
This would mean compression issue which would be a huge problem as an engine rebuild is out of the question for me at the moment :/

The other thing I observed was with the injector hard lines.
I put my finger on each of the hard lines near the injectors and I felt the pulsating fuel in all but one of them. It was cylinder nr. 3.
I thought maybe air in the fuel system so I loosened the nut on the injector (with a still running engine) and fuel started to squirt out from the nut. I let it run like that for about 20 seconds than tightened the nut.
When the nut was loose I heard as the cylinder stopped igniting and when I retightened the nut it started working again. (this was with warm engine)
So fuel is going to all of the injectors and all of the injectors do open.
Maybe the spray pattern is so bad that it needs either a hot engine or a hot glow plug to ignite?

I know a compression test would be the easiest but I don't have a tester yet.

Do you guys have any tips I could try without showering the thing with money?
 

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Discussion Starter #2
Almost forgot.
I checked for blow by with the oil cap. I do have some blow by as the cap dances around but it wont shoot off the cap so I guess it's not catstrophic. The oil check needle also stays in place. Actually when I pull it out I can't feel any gas coming out of it's tube)
 
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