cam sensor issue

Discussion in 'TDi - SEAT Diesel specific topics' started by teeth2k, Apr 2, 2017.

  1. teeth2k

    teeth2k Full Member

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    I'm having this cam sensor issue, vcds throwing me error
    Camshaft position sensor (g40) implausible signal.
    Not I'm doing my research on the web and trying to find possible solutions, have already replaced the sensor but fault still present.

    Question is until I can find the fix without throwing buckets of money at it is

    Car starts after about 5 turns with the cam sensor unplugged, although a little lumpy but, will running it with the sensor unplugged cause any damage?
     
  2. Speed-FReek

    Speed-FReek Senior Member

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    The cam sensor is needed so the ECU knows which stroke each of the pistons are on (induction or compression).

    The other important sensor, the crank sensor enables the ECU to determine the engine RPM and more importantly, when each piston is at TDC. However, the crank sensor alone will not enable the ECU to determine whether a particular piston is on an induction stroke or a compression stoke. This is where the cam sensor comes into play because it enables the ECU to determine this missing piece of information.

    If you run without a cam sensor then the engine will usually run (as you've already discovered), but it can take longer to initially fire up (again, as you've discovered) and it will generally run in "batch" firing mode which is less efficient than "sequential" firing mode that occurs when both the cam and crank sensors are both working together.

    You generally can't do any damage running without the cam sensor working although you may notice a difference in engine running and throttle response/power. Fuel consumption may also go up slightly but this isn't always the case. It depends how the ECU has been programmed to perform batch mode firing.
     
  3. teeth2k

    teeth2k Full Member

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    Thank you very much indeed for you reply, the fuel economy on long runs is about 45mpg at present, I have installed the dark side egr delete last week and that has helped with power.
    I guess its going to be one of these long to get to the end of problems
     

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