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Anonymous Posted on Jan 06, 2013

2003 mountaineer V8 Temp gauge jumps to hot not over heating. Replaced thermostat, no change

2003 mountaineer V8 Temp gauge jumps to hot but not over heating. Replaced thermostat, no change. Engine reduces power and check engine comes on. If I turn car off for 10 seconds the temp returns to normal.

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ANDRE

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  • Posted on Apr 15, 2014
ANDRE
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Can you have a feel of the radiator once you start in the morning is it hot all through once the thermor opens, does the fan comes on once it is hot. Do one thing put the A/C on and go for a spin see what happen.
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  • Posted on Jan 14, 2013
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The Engine Temp. sensor is bad. it is under the intake manifold. if there is a miss also check under the coils over the spark plugs. If there is Coolant in the spark plug holes .then the intake gasket is leaking. The intake manifold needs to come off to change the coolant sensor. When off look for corrosion on the cylinder head at the coolant port. If there is corrsion then the cylinder head must be replaced.

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Anonymous

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  • Posted on Mar 10, 2011

SOURCE: I have a 2000 Mercury

Hi,

The overheating and lack of cabin heat both point to a failed engine thermostat which would be stuck closed. At the warm up stage, the coolant stays in the engine block to bring the engine to efficient operating temperature, then it opens and circulates the coolant through the radiator and heat core. If the thermostat is stuck closed, the engine will overheat, and coolant will never reach the heater core, and you will not get cabin heat.

Blinking oil light at idle which goes away during driving could be a low oil level, but may also be a drop in oil pressue. You could have a clogged oil fliter (at best) pickup tube, or a failing oil pump.

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Anonymous

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  • Posted on Mar 10, 2010

SOURCE: False temp reading

you will find that there is nouthing wrong all that is a bad reading due to a faulty body earth! seen it all before! just check your body earth points it will be one of those loose! or corroded!
think it's one underneeth the drivers side foot well plastic pannel I think? but it is definetly one of them stop worrying! you will find it easy now you know what it is!
Hope that helps (shuld do!)

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