[CarFreek]

When i did my cylinder head I had to disconnect knock sensor-Since rebuild Im getting check engine lite past 2000-2500 RPM-Pulls code 52-Knock sensor circuit-Before rebuild, no matter how bad it pinged, it never tripped knock sensor-Car is timed at 10 btdc, cams are indexed-Can you put that plug on backwards?-Is the plug under Intake/next to fuel filter the Knock sensor? I drove the car another 40 miles tonite- gonna drive to work tomorrow and see how it goes but so far engine runs good-Can you defeat sensor? tia-Mike p

 

[CRF_Rider]

I am getting the same thing intermitantly after my rebuild. Code 52 means an open circuit or short. I am thinking my knock sensor is going bad.

 

[CarFreek]

I got under car this am to do post head oil change-pulled the under cover and pulled plug off sensor-WEIRD plug-Looked like I had it rotated 120 deg-Snapped it back on-Dont remember it snapping on when I connected before-I dont know how long the computer looks for sensor, but it lites within a minute of start up-So I may not have connected it rite-also, it was the only wire connected to engine when i grounded battery o engine with breaker bar-Keep ya posted-Mike

 

[Dave A.]

So...what was the reason for disconnecting the knock sensor?? I had the knock sensor go bad on my 85 and I swapped it for a used one from the j-yard and no more CE light.

 

[CarFreek]

When I pulled Intake off the wire for knock sensor was looped thru it-since I didnt disconnect harness at ECU-I had to disconnect all the harness wires to get all the parts off-Went to NIX99 today and got another sensor-just came back inside from putting it in-Even w new sensor, still CE lite-So my options are ECU or the wire melted during electrical backfeed from grounding out battery by mistake-Hell, I didnt want to disconnect that thing-it lives next to the suicide hose-Gonna try running a jumper from ECU to sensor to get a go/no go on wire function-Really am not yet ready to believe that ECU is bad-Mike P-BTW-Even w car jacked up I dont know how you guys tap the hole for the pre 85 cars w the block in the car-Thats some talent!

 

[Dave A.]

The jumper wire test sounds like a good approach.