moto.dev

Took a long hiatus from trying to figure out the issues with this car and came back to it with a fresh start. All other codes have been fixed except for cylinder 1-2-3 misfire and I have discovered absolutely no compression in those cylinders. Cylinders 4-5-6 all have good compression. I made a post last year explaining the whole situation with this car, but I had glossed over the compression tests. I am unsure what would cause this other than a head gasket issue, or stuck valves. Neither of which seem very likely, but I am more than willing to consider and/or try anything to further my investigation into this. ANY help is greatly appreciated!!

spectre6000

The aforementioned post last year:
https://5series.net/forums/e60-discu...etimes-152798/

You mention fuel smell, but fuel pressure is good. Combined with 0 compression, I'd check that the injectors are properly seated in the head as my first step. Honestly though, I'd just tear it down, and start poking around with everything that involves a hole in the cylinder; valves, plugs, injectors, gaskets, and finally rings. It seems odd you'd have decent compression on one bank and zero on the other. Mayhap it was parked due to something unrelated to the zero compression issue, got partway through the job, and then dude died. I haven't had time to really dig into my own yet (which is an N54 anyway), but if you can get it running with the valve cover off (may not even be possible on an engine this modern, just something I've done in the past with similar maladies to great success), it might help expose the issue.