[V8] RPM Sensor

[Bob Moy]

Both crank position and rpm sensors are magnetic sensors.  As we all remember from high school physics a magnet will lose its magnetic properties as it heats up.  The magnetic properties are restored once the magnet cools down.  The crank positions sensors reads a pin that is pressedinto the flywheel. The crank sensor is used to tell the ECU when the engines is approaching TDC.  The speed sensor reads the teeth on the flywheelproducing an AC current which is used by the ECU to determine the engine RPM.  A quick check for the rpm sensor is when the car stall/dies, crank the engine and look at the tach, it should bounce while the engine is crankingHTHBob Ahhhh, yes.  I forgot the holder part came out with the heat shield.
Anyway, you can't really get to any part of the sensors for any kind of
cleaning operation without removal.



At 08:28 PM 3/5/2006 -0500, Dave Head wrote:
>Actually, the sensors are mounted with 8 mm short bolts to the alignment 
>housing. The long bolts go through the heat shield and the housing and 
>fasten both to the block.
>
>Kneale Brownson wrote:
>
>>The sensors slide into a housing and are held in place by the bolts that
>>anchor the heat shield.  I don't think there's any way to "clean" them
>>without removing the assembly.
>>
>>You're right that its a PITA.
>>
>>
>>
>>
>>At 11:28 AM 3/5/2006 -0500, Speakoutprod at aol.com wrote:
>>  
>>
>>>Jeff,
>>>
>>>Did you have to replace the sensor or just clean it?  I hear these are  a 
>>>bitch to replace.  If you just had to clean it, was it still hard to do,
 or 
>>>could a high-pressure hose do the trick?  If I recall, these sensors are  
>>>located 
>>>underneath the car.
>>>
>>>My RPM sensor is currently acting up ONLY when the car reaches a certain  
>>>temp (usually on warm days) and once the car has cooled down, the sensor 
>>>works  
>>>again.  Not particularly good if your car stalls on a railroad track and a  
>>>train's coming.
>>>
>>>    
>>>
>>
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>>  
>>