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quorntobewild
13-02-2023, 12:30 PM
Hey people
Can I pick your brains.
Turbo went on Thursday, like a **** in a sock so lots of oil and smoke everywhere, towed home.
Fitted a second hand one, scanned for faults an old cam position sensor fault came up so I had a spare one so swapped that too.
Scanned again no faults, started on the button best it's started in ages so guessing the cam sensor helped, ran for 20 mins scanned again no faults at all.
Engine off have lunch lol.
Ran for a few mins then took it round the block, revved through the roof like the throttle was stuck, pushed it home, scratched my head for a few, then tried to start it and it started on the button again, ran it for a while( still no faults) revved it a few times every 20 secs or so revs just go full throttle from 2000 to max nearly as fast as I can pull the key out.
I'm gonna go check all the vacuum pipes and connections I've touched(can't see anything)
So revs through the roof till I pull the key and as it revving lots of smoke.
Still no faults at all on vcds
Any thoughts or ideas would be greatly appreciated.
My heads banging with this.
Quick update, checked for metal in oil incase the injectors were being held open not one fleck, checked throttle pedal position with vcds and all looked good.
Disconnected the battery for an hour and I've been unable to repeat the fault since, an hour or so sat on the drive revving, only driven a few miles so far, no MOT till tomorrow and RAC won't recover me without MOT so better to be safe than sorry.

Crasher
13-02-2023, 03:45 PM
That is called Diesel runaway, there is oil an the charge air system and when this gets pulled up during hard boost the engine runs on its own oil. You are lucky your shut off valve works as if not, the only way it stops is when when it runs out of oil and seizes.

quorntobewild
13-02-2023, 07:03 PM
No oil in the air system.
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PaulD66
24-04-2025, 06:24 PM
Noticed your post from 3yrs ago. I have this problem. Did you get to the bottom of it

quorntobewild
24-04-2025, 08:24 PM
Noticed your post from 3yrs ago. I have this problem. Did you get to the bottom of it

I think it was oil in the intercooler getting sucked up, buy the time I came to this most of the oil was gone, I was advised to put a small hole in the intercooler right at the bottom to let the oil out then put a screw in the hole, I had some nice big wafer head self drill screws so I used one of those, I got a couple of tablespoons of oil out.
I think it would generally be oil in the air system somewhere or throttle position but that would show in vcds.
Good luck buddy