I recieved a trouble code from the computer saying my knock sensor ...sucked. I had gotten one from the junkyard, and noticed when i replaced it, one had a hole in the bottom *where it sits against the block* and my replacement one did not. The computer didn't like either one. ....

 

has anyone heard of this being a problem?

 

what does the hole do?

 

is there a reason i need one with the hole, or without?

 

do knock sensors go out often?

 

could it be the circuit?

 

its my only trouble code, and after a 3 1/2 month rebuild, this is my only snafu... i'd like to get that stupid light off the dash!... without the use to electrical tape

 

thanks!!!

Luigi

I have a 91 MT and a 92 AT, both EA82 non-turbo and they don't have knock sensors. Did only the turbo EA82s have them? I know a Legacy I used to have did too.

I have a 91 MT and a 92 AT, both EA82 non-turbo and they don't have knock sensors. Did only the turbo EA82s have them? I know a Legacy I used to have did too.

 

yes its to prevent damage. the knock sensor *from what i understand* hears a "knock" and retards the timing on the engine.... thats as far as i know....

Yes you are correct. Only Turbo'd motors have them. I think there is a one wire knock sensor and a two wire knock sensor and the difference is on the years of turbo EA82s. the early ones had a single wire and the newer ones had a two wire knock sensor. or it could be the other way around. its located on the back of the top of the block below the pitch stopper on just on the passenger side of the middle of the block

I know the early (up to '86, flapper MAF) and late ('87+, hotwire MAF) EA82T's use a different style knock sensor, or at least they look different and the wire connecter is different. My stock '87 has the hole in the bottom, I've got a early one I could check too.

 

If thats any help

Gary

Yes you are correct. Only Turbo'd motors have them. I think there is a one wire knock sensor and a two wire knock sensor and the difference is on the years of turbo EA82s. the early ones had a single wire and the newer ones had a two wire knock sensor. or it could be the other way around. its located on the back of the top of the block below the pitch stopper on just on the passenger side of the middle of the block

 

That reminds me... the late style is one wire and the early is two wire, tho the second could just be a ground.

 

The early set up is a stand alone with a vac type distributor, the later set up has the timming retard built into the ECU

 

Gary

yeah i definitly have the single wire, and its interesting,.....the one i have now does not have a hole in the bottom, but my old one did... maybe this is my problem...

Figured out the problem was a broken wire in the freakin wiring harness... replaced the wire going from the comptuer directly to the knock sensor, bye bye check engine light.

 

YOUR CONNECTION IS ONLY AS GOOD AS YOUR WEAKIST LINK!

 

check your continuity!

Figured out the problem was a broken wire in the freakin wiring harness... replaced the wire going from the comptuer directly to the knock sensor, bye bye check engine light.

 

YOUR CONNECTION IS ONLY AS GOOD AS YOUR WEAKIST LINK!

 

check your continuity!

 

check engine lights are thrown for a component CIRCIT not an individual component. Good job finding the problem.