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Topic Review (Newest First)

  • 08-09-2010, 06:17 PM

    Re: Sorted after over a year!

    My CAS was new, I even got another one and tested it, made no difference. It was definitely the crank pulley/dampener, the car is running sweet now with no cutout issues at all.
  • 08-06-2010, 12:34 AM

    Re: Sorted after over a year!

    When mine acted like that, it was the crank sensor (M50 525i). There was no fault code, just the engine would shut off completely at 4300rpm. Came back to life as soon as revs were below 4300.
  • 08-01-2010, 06:32 AM

    Sorted after over a year!

    Nope nothing to do with thermostat, sensors all ok, the only thing that kept coming up on the computer was the crank angle sensor. Thing is the sensor was new genuine and measures in spec.

    Drive it and not get the cutout, IE treat it gentle for 30 mins to really warm it up and the code doesnt get tripped. Take it out cold and push it till the cutout happens then go back and check, code is there.

    Finally I found in the archives a guy who had the same issue 8 years ago! And spent 6 months testing and changing every godamn sensor on the car. Eventually he had the CAS scoped and found the signal it was getting was varying when cold, and as the revs rose the signal would drop out and in causing the DME to panic and shut off and on...

    Turns out its the damn crankshaft pulley/dampener!!! Soon as I put a white light on mine I could see the damn thing running out of round significantly. Trip to the wrecker and 110 bucks later I had a replacement from a very low mileage car that looks like new, got it bolted on and bingo, perfect again! The new one is rotating out of alignment a little like they all do, but its not out of round which seems to be the issue...
  • 07-29-2010, 01:40 PM

    Re: Violent cutout during acceleration

    Is the replacement thermostat a 95 degree?
  • 07-26-2010, 07:03 AM

    Violent cutout during acceleration

    when warming up.

    540i RHD, 1994 model.
    Warm car up for a minute, drive off, nice and gentle for 10 mins or so, engine temp comes up quick as I have new thermostat, g/box is freshly rebuilt and running sweet, car itself runs sweet, but if you try to accelerate too hard before the car has been driving at least 30mins, it cuts out violently on acceleration, usually around the 3500-4500rpm mark, like someone is turning the ignition on and off, or the ASC valve is closing and opening rapidly. Once really hot no issues.

    I thought it might be the Crank Angle sensor at first, it was new a couple of years ago, genuine, swapped it over and no difference so swapped it back.

    Borrowed an old computer from my mechanic and hooked it up cold, the temp sensor is reading ok, 17 deg C cold and 3.7 ohms, within 5-7 mins of idling its at 60 deg C and 1.8 ohms.

    Someone must have some idea on what else to check that could be causing this, its very damaging to the driveline if I forgot and push it a little before its been running 30 mins.

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