Toyota Help

[RD TRCTR]

I've got a 1985 'Yota with the 22REC engine. I am currently getting the MIL (code 12) for the knock sensor. The only issue is that the engine does not have a knock sensor. I've had this truck for a while now and all of a sudden this code shows up. I did just recently replace the TPS. If any one can provide some help it'd be greatly appreciated.

[4RunnerAdam]

You mean the knock sensor has been removed?

It should be near the oil filter. Has a green wire going to it.

[RD TRCTR]

Is the truck supposed to have a knock sensor? It ran just fine with no check engine light until here recently. I guess I'm confused as to why the CEL wasn't on and then all of a sudden it came on. Thanks for the help.

[4RunnerAdam]

Yup, should have a knock sensor. Why it worked without one I don't know. Parts store are showing a new knock sensor for $155 :eek: I'd find a used one.

[krawlin85toy]

Had the same problem at 1 time,could be a knock sensor,tps,and or dist. my problem was the wire to the knock sensor has to be shielded after I replaced the end and have trouble free since. 4tears knock on wood!

[RD TRCTR]

I took your guys advice and finally looked for the knock sensor today. I couldn't find it. I looked all over the intake side of the engine. I then called a dealer and gave them the VIN. According to them, it should have a knock sensor and it's located on the exhaust side of the engine (?). I figured that since I had replaced the TPS, that maybe I didn't set it right. So, I followed the directions in the repair manual and online. Took the truck for a drive, CEL is back on for code 12, knock sensor. Do I need to pull the plenum to find the knock sensor? I did replace the injectors in January. I also found the connector that goes to the knock sensor and it has a decent amount of grime in it leading me to think that it has never been hooked up. The truck was built in November of '84. Thanks a lot for your advice.

[4RunnerAdam]

Knock sensor is located on the passenger side of the block below center of intake manifold. I think some of the newer (or maybe older?) 22r's had a different location. Definetly don't need to remove the manifold.

Could also be a bad ECU.

[RD TRCTR]

I had the chance to look at another '85 fuel injected truck over the weekend. It did not have a knock sensor either. So that leads me to think that maybe mine shouldn't have a knock sensor. The MIL is still on and I have pulled the EFI fuse and let it set many times over night to reset the ECU, but the MIL comes back on as soon as I drive it. Can the problem be an ECU? And, if it is, how does the truck still run (and run as well as it is)? I greatly appreciate y'all's help.

[krawlin85toy]

the knock sensor location: if you look inside the pass fender well it is located to right and slightly above oil filter,has a round single wire plug, if not muddy it should be a off white color. Are you sure its a code 12? ARE you jumping E1-and T with jumper wire? Double check code cause 12 is RPM signal. AREAS TO LOOOK ARE DIST. CIRCUIT,DIST,INGITER CIRCUIT,IGNITER,ECU, these are from toy service manual. Knock sensor code is 52 or 53

[4RunnerAdam]

Not sure where your getting your DTC info from, but according to my 1985 truck and 4Runner factory service manual a code 12 is in fact the knock sensor.

First thing I'd try is getting a knock sensor on there. If that doesnt work, try a different ECU from a known working truck.

[maddhatter]

Couldn't you fix this all with a small pease of black tape?:D

If it wheels wheel it!!!!!!! If the plugs look ok and it runs good your just shooting yourself in the foot screwing with it. just my 2 cents.

[RD TRCTR]

Thanks 4RunnerAdam for clearing up the code definitions. I saw a similar conversation on 4x4wire.com.
I would just install a Knock Sensor, but they're $155 from the dealer and they're only available from the dealer. I haven't been able to locate a used one. Since used ECU's are much cheaper, I plan on going that route to start the trouble shooting. I am looking for a used knock sensor, used ECU or both.
The truck runs fine. I would do as MadHatter stated, but I want to get rid of the truck and it'll bring a lot more without the MIL on.
Thank you all for your help.

[4RunnerAdam]

Don't have any buddies with a 22re? You could try a known working knock sensor and ECU from that truck to make sure that fixes it.

I would find a knock sensor used. First I would try various 4x4 sites for sale sections, like 4x4wire.com, yotatech.com, and pirate4x4.com. I GUARANTEE you will find a sensor and/or an ECU for cheap on one of the sites.


What about some members on the board here? I bet you Rob (Fabricator) has some parts trucks he would sell some parts off of, or possibly even a running 22re truck he would let you experiment with.

[fabricator]

got something you could try
but i wouldn't sell, cause my truck is a RE truck
save them parts for it......

Did you ever find the place to put the sensor if you had one to try?
A friend swapped motors that didn't have a spot for a sensor
so he mig welded something right to the block and screwed the sensor in to.
Sounds crude but it worked.