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Discussion Starter · #1 ·
Exactly what does 'pinging' or 'knocking' sound like? My knock sensor is dead and I am waiting to find a place to replace it cheap... I don't think I have heard pinging or knocking but should I not drive much until i get it fixed?

About how much will a knock sensor cost?

The CEL only goes on when I am in a lower gear than needed.. (rpm's just above 2000) and usualy for a short bit and then it goes out... it goes back on and off if you stay in that gear.
 

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The conditions most likely to cause detonation are at low RPM, under high-load with crappy gas: put the car in 4th gear at 30MPH and floor it. If you hear something that's vaguely like marbles in a tin can, that's detonation. You may only hear a hint of it as you put the pedal down.

In small amounts detonation won't hurt a normally aspirated car. However, prolonged detonation can cause problems.

I can't say how much a sensor will cost but it's likely not cheap and replacing it is tough: the intake manifold and a coolant pipe must be removed from the V6 to get at it. Have you actually pulled a code 05 from the PCM?

Finally, when the PCM senses a bad knock sensor (e.g. the sensor is shorted to +5 or to ground) or if it hears a ton of knock activity, it will revert to using a spark table that has much less advance under low RPM/high-load conditions, precisely because of your concerns. If this is true, you may not hear knock under the conditions I mention above because the PCM is using the low-advance table.
 

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Discussion Starter · #4 ·
five short flashes

Well when I pulled the trouble code it was 5 short flashes which i was told was the knock sensor.

What would you reccomend doing? should I take it to a shop? I really don't want to spend that much money.. but I don't want to have to rebuild an engine!!

Thanks for your help
alex
 
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