A special case

[IRONMAN]

So I have code 52. Yes That one. And yes I have looked and search first. but let me explain.

I had code 52 so I bought two brand new sensors. Then wound up having to replace the engine so I got the only engine I could (GE).
So now I have one knock sensor hole. So I tried some things.

-wire both lines into one sensor
-do complete rewire
-ground shielding
-swap the sensors out multiple times
-wire in both sensors seperately and free rev to look for code just in case
-Then I got desperate for a solution and pulled the sensors, manually grounded them, wire both sensors seperately, ground shielding, and wrap them in shock resistant foam and isolated them from the engine. I was hoping that if everything was perfect they couldn't give a code.
-Then after that I checked the ecu for any bad resistors or capacitors. And it was perfect.



Knock sensors are brand new, wiring is perfect and done by the book, grounds are perfect, ecu is mint.
I have run out of ideas. Someone please help.

 

[Dan_Gyoba]

The 7M block has 3 bosses for knock sensors. The GE block has the center one tapped, the GTE block has the front and rear ones tapped, but all 3 bosses exist on all of the blocks.

Knock sensors are essentially microphones. The ECU "listens" for frequencies that happen when knock occurs, and if it "hears" them, it retards timing. More than that though, it "listens" for ignition events. If it does not "hear" them when it expects to, on the specified channels, it sets code 52, assumes that the knock sensor(s) aren't connected, and goes into limp home mode.

I believe that you can just tap the threads into the bosses. I think next time I'm working on my engine, I'm just going to measure the threads, so that I have an answer.

 

[jetjock]

....pulled the sensors, manually grounded them, wire both sensors separately, ground shielding, and wrap them in shock resistant foam and isolated them from the engine....

A special case alright...

 

[suprarx7nut]

So I have code 52. Yes That one. And yes I have looked and search first. but let me explain.

I had code 52 so I bought two brand new sensors. Then wound up having to replace the engine so I got the only engine I could (GE).
So now I have one knock sensor hole. So I tried some things.

-wire both lines into one sensor
-do complete rewire
-ground shielding
-swap the sensors out multiple times
-wire in both sensors seperately and free rev to look for code just in case
-Then I got desperate for a solution and pulled the sensors, manually grounded them, wire both sensors seperately, ground shielding, and wrap them in shock resistant foam and isolated them from the engine. I was hoping that if everything was perfect they couldn't give a code.
-Then after that I checked the ecu for any bad resistors or capacitors. And it was perfect.



Knock sensors are brand new, wiring is perfect and done by the book, grounds are perfect, ecu is mint.
I have run out of ideas. Someone please help.

You have a ge motor... And a GTE ecu? Perhaps a ge ecu is a logical solution to thus conundrum...?

Sent from my Galaxy Nexus using Tapatalk 2

 

[supraguy@aol]

To my knowledge, all three bosses are tapped on gte blocks.

 

[IRONMAN]

The Ignition listening makes sense.

Let me clear one detail up though.
The car is a 1988 Toyota Supra Turbo Targa. The only GE part is the block.