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Mercruiser 8.1 L Horizon gas engine

Discussion in 'Engines' started by phildehazya, May 17, 2010.

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  1. phildehazya, May 17, 2010
    #1
    phildehazya

    phildehazya New Member

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    Jan 6, 2010
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    Location:
    Seaford NY
    Hello- I have a 2001 , 370 HP gas engine with only 300 hrs that seems to have sensor problems: water pressure and coolant temp (so far). Motor goes into "safe mode" even when nothing's wrong-except for bad sensors. "Safe mode" means 1000 rpm, no throttle response above that, until the issue is fixed. NOT SAFE.

    Any way to bypass "safe mode" if I determine that systems are nominal?

    Thanks for any advice.
  2. NYCAP123, May 17, 2010
    #2
    NYCAP123

    NYCAP123 Senior Member

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    Sending you a PM.
  3. about time, May 17, 2010
    #3
    about time

    about time Member

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    water pressure and coolant temp are related, are you sure this is a sensor problem? Water pressure sensor is optional on alot of engines, I dont think that alone would cause the brain to go into safe mode. Coolant temp would. Have you tested the sensors? You will be better off fixing the problem than trying to bypass safe mode. If other unrelated sensors are giving problems or intermittent problems, check you grounds, also check capacity and integrity of you batteries.
  4. CSkipR, May 18, 2010
    #4
    CSkipR

    CSkipR Member

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    If you have dual engines just switch the other engine sensors and see what happens. This will tell you if its the sensors or not. Also look for a wire inside the sensor cap that might be loose.
  5. about time, May 18, 2010
    #5
    about time

    about time Member

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    NYCAP123, would really like to know if you know something I dont about bypassing "safe mode", to get home for example.
  6. NYCAP123, May 18, 2010
    #6
    NYCAP123

    NYCAP123 Senior Member

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    No. Had seen the problem on a couple and seemed to remember it was a recall issue back then. So I referred phildehazya to a local service manager who had handled the repair and was very familiar with the situation.
  7. about time, May 18, 2010
    #7
    about time

    about time Member

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    are you familiar with the repair? perhaps you could enlighten me
  8. NYCAP123, May 18, 2010
    #8
    NYCAP123

    NYCAP123 Senior Member

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    Been too long and I'm not a mechanic, but I seem to remember it was a programing situation not a sensor problem.