I'm helping a friend with her 86 SR5 4x4 truck with the 22R-E engine (US emissions), manual tranny, 231k miles.

I finally figured out the how to get the CEL to blink the codes (thanks to this forum) and I got 12 blinks which is the knock sensor. Where is the darn thing? The Haynes manual doesn't mention it or show where it is (of course).

So does this mean the sensor is bad or that the sensor is picking up a knock? Engine sounds fine (for 231k miles) but I think it had a headgasket done a couple of years ago.

I reset the light and we'll see if it comes back.

If it comes back is it worth pursuing on an engine of this age as long as it seems to be running well? Thanks.

 

Anyone?

 

The sensor is located behind and slightly above the oil filter.

 

http://www.lcengineering.com/TechNotes/TechNote14.htm

there is a nice little diagram that should help. scroll down, you shouldn't need to relocate it, but for a reference to the stock location

 

Thanks for the replies...now I know where it is.

Does anyone know if the CEL means the sensor is bad or if it it's just picking up a knock? Thanks.

 

It does not mean it is bad. I means there is something going on that need attention. It could be a bad/broken unconnected knock sensor wire, a bad knock sensor or an actually knock in the motor that would require a tune up to fix.

You dont want to replace the sensor unless you have to cause there like $180.00

 

Thanks. That's exactly what I wanted to know.