StupidRunner92

so my trucks been running extremely rough the past couple weeks. i crossed the TE1 and E1 and flashed a knock sensor problem. i know that i have to pull off the plenum to get to the knock sensor and i have read different posts on it. my question is what else should i do while i have it torn apart? im assuming it will be easier to do timing belt and waterpump as well as valve cover gaskets while i have it that far down. any other help would be GREATLY appreciated! thanks

Old Gray Bastard

When you replace the knock sensor you should definitely go to the dealer and purchase the short connector harness for the knock sensor. I believe it was under 20 bucks when I bought one last. It's just a peace of mind thing, that harness heats up and cools down and gets brittle after awhile. And you might as well do a timing belt and component kit, valve covers, cam seals, front main, replace all the copper washers on the banjo bolts in the fuel rail, and injector seals while your there. Not necessary if it doesn't need it, but like you said you'll already have it apart.

Old Gray Bastard

By the way, I've seen a couple people do this and I've tried it myself. I was told it was the supposed dealers alternative solution to the knock sensor replacement. They ended up bolting a bracket to the side of the block under the number six cylinder. The knock sensor threaded into the bracket. They lengthened the factory harness and unplugged it under the fuel rail and re-routed the wiring to the new knock sensor location. It didn't work for me, but it's a lot less work if you wanted to get other peoples opinions on this method of simply leaving the bad knock sensor where it is, and relocating a new one.

loko ino

Definitely replace the knock sensor pigtail.
When I did my head gaskets it was suggested I replace that because it is cheap and they tend to fail from being exposed to so much heat...glad I chose to do it. The original one was so brittle it fell apart in my hands when I tried to straighten it.

ksti

I'd suggest replacing all the hoses at back of motor (firewall side).
There not easy to do with plenum on, so now's a good time while apart.

StupidRunner92

Im.hoping this well fix my problem. Before the runner quit really running, it had a power band at 3k rpm.Until u hit 3k it was extremely sluggish but the second u hit the gas itd put u back in the seat! Every gear is like tgat

scope103

Actually, there is probably nothing wrong with the knock sensor. They're very tough, and there isn't much to break. The pigtail, on the other hand, is almost certainly junk, and if it breaks you'll get a knock sensor code. So you will replace that no matter what else you do.

The bad news is that there really isn't any way to test a knock sensor. So you can take a chance that I'm right, and just replace the pigtail. Then if it doesn't work, well, you still don't know if it's the sensor or other wiring. Or you can just pony up the $140 http://www.toyotapartszone.com/oem/t...615-50010.html and eliminate that as a possibility. Your choice

I've heard some folks on this site claim that mounting a replacement knock sensor to the lifting eye or some-such is just as good as where it was mounted in the factory. Sorry, I don't believe it. The Toyota engineers are no dummies; why would they mount the sensor in a near-impossible location unless they had to?

AZSPEED

I messed with my ks for months and nothing worked the only thing I didn't try was a new computer decided on doing a Lexus swap instead of spending any more time on the 3.0

StupidRunner92

Before i tear this apart...does my 3.0s symptoms sound like knock sensor problem?

scope103

If you get the code, your ECM hasn't heard from the Knock Sensor. That doesn't tell you if it's the sensor or wiring or ground or something else, but yes, you do have an issue in your knock sensor circuit.

"running extremely rough" can be, oh, about 100,000 different things.

When the ECM loses touch with the knock sensor, it dramatically retards the ignition to avoid pre-detonation (which could blow a hole in the top of a piston). The main symptom of that is reduced power (but even that could be masked by someone cranking up the base timing).

You're going to need to fix that code or it will never run right. As advised, the most likely cause is a bad pigtail, but once you start frying wiring the problem could be elsewhere.

Good luck!