lftd_86_yota

Any help with this issue would be greatly appreciated.

I have a 1988 4runner with the 3vze. As some of you may or may not recall the truck was sitting in a field for three years after a fresh rebuild, (P.O bought a new taco after rebuild) anyways. truck has been throwing famous knock sensor code at me since I got it. I finally broke down and replaced both the knock sensor and the brittle hard subharness at the same time. after everything was back together and running great I was thrilled, then when I reached the neighbor's mailbox about three houses down (head mechanic at local toyota dealer) THE LIGHT CAME BACK ON!! I went back home and used gf's bobby pin to cross terminals.. knock sensor... I won't lie I think I cried... what gives?? toyota dealer says it could be in the computer itself, is this feasable? also as soon as light comes on truck loses 20% of power, neighbor says it's because the computer runs in "fail safe" mode screwing with a/f mixtures. any other suggestions? also 88 3.0 a/t computers seem very hard to find, as the truck will only accept an 88 3.0 a/t computer. (so i'm told) Thank you and sorry for the length of detail.- Josh

OutlawMike

Sorry to hear about thet trouble, especially after pulling the intake off to get to the darn thing.

What torque did you torque the knock sensor to? I could never find a torque spec for it in my manual. I ended up going to the dealer and getting the spec from a master tech, 56 inch-lbs.

If you did the sensor and pig-tail, then you might have a bad connection in the harness itself. Hard to diagnose, but it could be a harness wiring issue.

Or, as you stated, the computer.

Good luck,

Mike

BT

There's a good chance it's a bad connection with the harness. I got lucky and lost my code when I cleaned up the terminals in the connector. But my code was intermittent, which usually signals a connection problem.

lftd_86_yota

pulled battery today and ran code again... 11 Power supply?? reset agian and took for a spin, (neighbor's mailbox) light came back on. code 52. is my cpu screwing with me? first time I've ever gotten code 11, but again, code cleared. btw, truck could idle for three days straight and the light would not come on, as soon as it hits about 1800k in 2nd it greets me EVERY morning.

Zinek

I think the Factory Service Manual has procedures how to test the knock sensor by back probing at the computer conection.

shore.runner

I have code 52 knock sensor on my 88 4runner 3.0 auto as well.

Seems we have the same problem.
Ive just left it, its been there since i got it and it runs fine.
When your light comes on does it sound like the fan shuts off? how soon does it come up once you start going.

93toyrunner

Did you ever figure this problem out I am still looking to get rid of my CEL 52.