tilac1

Where is the wire and connection from the knock sensor located? I know the sensor itself is buried under the intake but where does it exit? I'm getting a code 52 and I'd like to check the connection. The sender and wire are only 2 years old (headgasket/rebuild).

Thanks,

Brad in MA

DH6twinotter

Hey Brad,

There is a little notch in the driver's side head that allows the knock sensor wire to come up through where the intake manifold and head meat. Your knock sensor wire is probably only about 6-8 inches long before it connects to the wire going to the wiring harness. If you look directly under and slightly to the rear of your throttle body you should see the wire and connection coming out between the #4 and #6 fuel injectors. It's pretty much the only wire under there other than the fuel injector wires.

Anyhow, hope that helps.
Have fun.

DH6twinotter

BTW,
Welcome to the forums!

tilac1

Found it thanks, but I think it my be something else. Noisy lifters setting off the 52 code?

tilac1

This a great forum. Thanks for the welcome.

DH6twinotter

Hey,

I got a code 52 a while back too. It turned out being a bad knock sensor. A bad knock sensor wire may also send a code 52 error. I'm not sure if noisy lifters would set that off or not though. Sorry I couldn't answer that.

Well, have fun.
DH6twinotter

tilac1

Thanks so much for helping me find the knock sensor wire and connector. It was really buried and hidden under the throttle body. I disconnected it, cleaned it, plugged it back together and problem solved. Your advice was very helpful. Thank you.

Brad

DH6twinotter

Glad I could help! That's what this forum is all about. I learned from other folks here. Awesome that it all worked out ok.

Have fun.
DH6twinotter

tilac1

My knocksensor problem went away for a month or so, now it's back for good. A new sensor and wire are $200 and it looks like an unpleasant job to R/R. Any alternatives?

gwhayduke

Order one online. The dealers online will save you some significant money. Google "discount toyota parts" and try several.

Astralplane

The part# is 82219-35010 for a whopping $9.92.
Also, they usually replace part# 90925-05047 (bi-metal switching valve) for $47.76 but I don't know why it needs replacement.

gwhayduke

Are you a Toy parts man Astral?

Astralplane

No, I'm not.
I just have a very thick stack of bills from the local dealership over the last 10 years.
I also happened to have my HG replaced again a few months back.
$1500 dollars worth of fun on a truck worth about $4000, but what else ya' gonna do?

oly884

It's a pain the the @$$ and a half! You have to take off the intake plenum and manifold. In order to do this, you have to remove the timing cover, and a fair amount of stuff under there, ie. timing belt, water inlet, etc.

I had to do it when I put my new engine in a while back on my old truck.

I'm not trying to discourage you, if you have the experiance, then go for it.

Other than that, I'm sorry to hear about it, and good luck.

Also, if you have any questions on doing this PM me and I'll be glad to help you though it.

tilac1

I know too well it's a pain in the @$$. Last year I had the heads off (head gasket) and replaced the $9.99 wire but not the knock sensor. I'd love to just hook up the new sender and wire and tape it to the intake. I'm gonna try it, what the hell. It's an old 1991 rusty pickup w/200K miles. I'll retard the timing and run premium if I have to. I do not want to do that job again.

I too have a stack of receipts $$$$. Ouch.

oly884

Well good luck on that man. I hated doing it again. The things we do to keep our yotas running!

oreomiddle

That also worked for me.Had a code 52 for about a year now.Found that pesky connector,unplugged it to find that the terminals on the vehicle end of the plug seem to be made out of brass.They were completely covered with a thick green tarnish.The other end has some kind of silver plating and seemed ok.I have not seen this much power from my truck for too long.Thanks for the lifesaver tip.

oreomiddle

it's amazing what a little sandpaper can do!

spiderwebbtc

I've already had the plenum off and finally found what I realize now is the knock sensor wire. Since it didn't appear connected to any kind of a sensor, I buttoned the engine back up. So let me get this straight: I have to also take off the intake manifold, timing belt, etc. to find the actual knock sensor? What else should I know before I try to find the knock sensor again? Does anyone have a picture or a decent diagram of how to do this job?

mattches

Spiderwebb,

Getting to the knock sensor is pretty straightforward, once you get the plenum off, you do have to take the intake manifold off as well. once you have the intake off, the sensor is screwed into the center of the block. It's the only thing in there. You probably can get it out with out having to take the heater cross-over pipe out. (you will see that when you get the intake off).
What makes you want to change the knock sensor? Code 52? have you checked the performance of your motor first, IE, fuel mix and plug condition? The knock sensor is picking up knocks that can be inaudible, due to pre-ignition or detonation.