I have an 88 F150 with a 5.0 Ltr engine, I have had an intermittant problem with pinging. I have read the fault codes and one of them states that the Knock Sensor was not tested.

I have changed the sensor before and it fixed the problem, however after running low on radiator coolant and boiling the engine about 2 months ago I have the pinging problem back again.

I am hesitant to spend another $160 Australian on another sensor without first testing the current one.

Does anyone know how to test the Knock Sensor?

 

Is code 25 present when you checked the Ecu for codes ?

 

Off the top of my head- I think I recall the book saying to hit the block in the area of the knock sensor with a hammer and check the timing with a timing light to see if the timing was retarted for a moment when the block was hit.


Dustin Siebert
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Thanks for the response, yes code 25 was present.

 

Clear the code & see if this test resets Code 25 . My manual says to use a 4 oz hammer , but Im sure any normal size hammer will do . With the engine fully warmed ,Run the Engine Running Self Test , after you have gotten the Dynamic Response Code ( This is when you breifly floor the gas pedal , Its not nessecary to goose the throttle as you normally would do ) tap on the manifold as close to the Knock Sensor as possible & see if Code 25 resets . Let us know what you find .

 

Thank you,

I carried out the test as you specified above, the code reset and did not re-appear after the hammer knocks. I still have problems to address but now know that it is not the knock sensor.