Crankcase pressure waveform

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wiki38andy
OneWave
OneWave
Posts: 29
Joined: Sat Apr 18, 2020 4:45 pm

Crankcase pressure waveform

Post by wiki38andy »

Nissan X-Trail 2.0dci (M9R) 2017 . Every few months MAF sensor, intake pipe and filter box gets oiled(blow-by gasses), and EML comes on.Compression 22-23bars , cylinder leak no more than 10%, cylinder walls look ok except few minor scratches. :D
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picowight
TwoWaves
TwoWaves
Posts: 164
Joined: Sat Oct 26, 2019 6:45 pm

Re: Crankcase pressure waveform

Post by picowight »

I don't see a scale on that, but I would hazard a guess at a sticky vent valve/PVC.
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wiki38andy
OneWave
OneWave
Posts: 29
Joined: Sat Apr 18, 2020 4:45 pm

Re: Crankcase pressure waveform

Post by wiki38andy »

Ambient pressure=800mV. Brand new oil separator with PCV valve. If PCV valve were sticky, should not interfere with all cylinders back pressure? I would rather point to vacuum pump pellet sticky/worn.
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