Well lads, latest info. I rang a diesel specialist about getting a compression and injector test done and he advised me to take the car out and give it a good run before bringing it in. A good run meant running it at 3000rpm for around 30 mins. I took his advice and headed off.
Very strange advice.
If you run the engine at 3.000rpm for 30min in 6th then it is very loaded, if you run it at 3.000rpm in 2nd or 3rd then it could overheat (both oil and water), either way bad thing to do.
If you want to clear the engine than you should do accelerations from 2.500-3.500rpm in 3rd, 4th or 5th gear (basically a bit harder driving), depending on what road allows.
10 minutes into the good run and my engine suffered overrun where it could not be shut off by turning off the ignition and continued to rev. Eventually the engine did stop running after about a minute. I managed to start the car again and drive it home without incident but have not started it since. An oil dipper stick check has revealed that the level has gone from max to min.
You are lucky that it started again (sometimes overrun can damage injectors), and lucky that it didn't consume all oil (that would damage whole engine).
Strange thing is that it didn't shut of instantly:
- either air closing butterfly on inlet is not working (in that case engine is probably shaking at turn off)
- either it was pulling air threw oil vapour recirculation system (but it has opposite direction valve that should not allow that
- If it used to consume oil even before this, than it could be leaking turbo, or worn piston rings.
- If it didn't consume much oil before that happened, than I guess this overrun is caused by overheated oil, probably pulled threw oil vapour separator...
After this what happened I suggest you:
- run the engine normally for some while to burn off all that oil from exhaust
Then do all the checks you can:
- check compression
- check oil vapour recirculation system (to see if it is recirculating anything or letting all vapours in the intake, to see if opposite direction valve is working...)
- check turbo for oil leak (if shaft has some clearance)
- check intercooler (if there is some oil in it which could come from turbo)
- check intake manifold (probably full of soot, clean butterfly on inlet, intake channels, inlet valves), as I suggested before if you don't want to remove whole manifold use some Wynn's EGR cleaner spray to clean the manifold when engine is running.
- eventually check injectors