rtbatchelder

code 52 knock sensor. i have searched this and tryed everything suggested , checked wiring from sensor to ecm for resistance. got new pig tail and sensor, added ground wires to block and body even tryed to relocate the sensor as a test. couple seconds of driving, code is back. i have heard a vacumm leak or leaks could cause this code even though it doesn't match the code discription. i did not have this code until after i had to swap out the throttle body. i have resealed the throttle body and am sure there is no un metered air entering there. and just did the gaskets on the intake and plenum, and valve covers. new pcv. i have another ecm that i tryed, but same same. any more ideas would help. i am at my wits end.

Thelast83inNJ

I assume 3.0 v6, the wiring sub harness under intake from sensor to connection at firewall needs to checked. It sucks I know, but maybe the wiring is frayed and you only have a couple of strands connected inside wiring jacketfrom being pulled on or moved. You will still have good resistance and/or voltage, but no opens or short to ground. Is the knock a Toyota part? Maybe it needs to be OEM sensor. The ECM ground needs to be on the cam cap bolt on the passenger head, not to the firewall or intake. That's all I got.

rtbatchelder

yes, sorry for the lack of info. 3.0L. new toyota sensor and pigtail. ecm ground at pass. cam cap is intact. i may run new shielded wire from pig tail at knock sensor to ecm and see if that works. thanks for your help. when i find out whats up i will post it here.

rtbatchelder

THANKS (Thelast83inNJ) for your help, i tryed a few things today, but what made my code 52 stay gone was, i un plugged the short pigtail to my new, relocated (temp. relocated) knock sensor and just used a jumper wire made of fuseable link wire, in between the sensor and the 4runner's wire harness connection. as a test and gave it a 5 mile test drive, no code 52. now i wonder, why the new wire and sensor didnt fix the problem. but with in the next weekend or so, i will properly install the sensor and make a new wire to the ecu. wierd. thanks again

Aaron G

Did your cel stay off after temp fix?

rtbatchelder

yes,i drove it 40 miles today to and from work. i didn't even use shielded wire on the temp. fix. im going to do it right though, i like my stuff clean and so on.

Aaron G

Rite on. Im having the same problem with my 1990 pickup. Did you try running the resistor on the knock sensor installed in the motor. And also what kind of resistor did you use. Im trying to get the damn thing smogged but this code 52 is killing me

rtbatchelder

no resistor, just reached under the intake, but my knock sensor wire was on the passenger side so it was hard, using 2 picks, i un hooked the the clasp on the connector. drilled a hole in the lifting hook mounted a new knock sensor to that. plugged in the new pigtail. but still got the 52!!!!! well after i got real mad i went out and removed the pig tail and used my jumper wire made of fueable link and gator clipped it in place, real temp. for a test. and so help me that did the trick. now i need to figure out why the new pig tail is not working. but for now no 52

Ric's 91

I used a jumper wire after reading this and it worked,I relocated my knock sensor and wire to my engine lift hook it work great for three days then code 52 again.the jumper wire ideal works my pig tail part of the harness was bad.

Ric's 91

CODE 52 realy suck's big power loss I couldn't even get up a hill lol,my truck is workin good now well not bad for having 437,700kms on it lol.

3.slowrunnin

My 93 3vze has had the 52 code ever since I bought it in Aug, 09, I checked the pig tail and the wire was not even hooked up to the ecm, I can see no trace of where the wire is supposed to go. I'm assuming that someone had the code and tried to bypass the knock sensor, I would like to try to bypass the sensor some how, can someone tell me if that is possible and what is the easiest way to do this. Thanks

rtbatchelder

as far as i know, there is no way to effectively jump or trick the knock sensor and i don't feel it should be done. the knock sensor helps protect the engine.the closest to not doing the knock sensor i would do and only as a temp. fix is what i had to do once. unplug the failed knock sensor, get a new one and mount it eles where on the engine easier to get to then under the depths of the intake manifold assem. i chose my lifting hook, i drilled a hole and monted the knock sensor there. again this is only a temp. fix until you have the time to tear into it right.

Ric's 91

Code 52 is back again I have allmost given up I do not want to tear the intake off.anyone want a parts truck lol, way to many kms on this truck, so a bad knock sensor there realy is a way to kill a toyota. the truck was fine till code 52 I was still getting 450kms to a tank of gas with 437,000kms on this truck.

Ric's 91

I lost this fight lol.

881stGenRunner

rtbatchelder...do you have any pictures of your fix that you did? I just had to rebuild the top end of my 3.0 and about 3 days after i finished, i got a code 52. Im experiencing NO POWER LOSS, but it is very very annoying having to look at that light. I have NO want or drive to get under the intake manifold and mess with it. Really needing some help here bud, thanks