Rough idle on hot start

dvarley

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E 320 T CDI
My 320CDI IL6 has developed a problem when the engine is hot and restarted after stopping for a few minutes. The engine shakes like a misfire, but after driving off and getting up to speed, it is okay and will idle fine. It seems worse when the outside temp is 30°+. It shows no faults and has had the mountings replace a year ago. I also get the common knocking noise at 1500 - 2000 revs when hot. I noticed the hot starting problem after filling up with supermarket fuel. Could this be the culprit? Where possible I use Total Excillium, which the car seems to like. Are there any other tests I can do to pinpoint the problem?
 

John Laidlaw

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Land Rover Discovery 4
Maybe an issue with the CPS (Crank position sensor) but it needs hooked up to a Star diagnostic first I guess to eliminate the obvious stuff
 
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dvarley

dvarley

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Star shows no problems, but the idle was okay when it was plugged in. It only does it just after a hot start and then it is okay until it is switched off and restarted before it has cooled down. CPS was replaced a year ago as it was faulty.
 
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dvarley

dvarley

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Star shows a fault. P0100-016 B 2/5 (hot film mas air flow sensor) plausibility 1. Air flow low at lower range of speed. Does this suggest that I need a new sensor?
 
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dvarley

dvarley

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I have just changed no 6 injector for a reconditioned one from a German supplier. Car back to normal. No tapping noise and fuel economy back to normal.
 

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