Sanchez

Here it is... '91 Pickup, 4x4, 3.0 V-6 Thanks for all the helpful advice and tips in the past... A truely awesome resource. Though with this problem I can't seem to find an answer... Here is what my problem is... Recently replaced the knock sensor, pigtail and eventually the wiring to the ECU. Still a code 52 - even after pulling the battery cable and efi fuses and relay repeatedly. It makes no difference in results whether the new KS is plugged in or not. Within a minute or by the time I hit second gear the CEL comes on. I am hoping that I can find an ECU to test on my system soon. Starting to affect my quality of life. Not to mention that winter is coming quickly... Has anyone had similar experiences? Thanks Tim

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shaeff

Doublecheck the wiring to make sure the signal wire isn't grounding out. If it is, you get code 52. There are only three possible problem areas.
1) Knock sensor
2) Wiring
3) ECU.

It's usually NOT the ECU. Most commonly, the wiring has failed. Did you torque the knock sensor to the proper spec?

__________________
My heatercore replacement writeup with pics.

-'94 Toyota 4X4, 22re, 31X10.5 BFG M/T's, 5 speed, MC rear bumper. (Winter DD/ off road fun)

-'95 BMW M3, modded/suspension, sticky rubber, back road monster (Summer DD)

-86.5 Toyota Supra, too much to list. (Never-ending project)

to4menon4u

i had the same problem and it turned out to be the ecu. i got a used one off ebay and it works perfect!

__________________
318,000 miles thats all i gotsta say
90' 2 door 3.0
32 11.5 15 <- no lift no rub
it even fixes itself!!! ( it also breaks itself )

Sanchez

Thanks guys... signal wire isn't grounded - sensor is torqued... I have a sneaking suspicion that this ecu might be done. I will know tomorrow... Fingers crossed...

Team420

I had the same problem and it turned out to be a vacuum leak... I think.

If the cel comes on as soon as the truck is started, it would mean no signal to ecu from the ks, but if it dont come on till say a min or 2 down the road, it could be unmeterd air getting in, and causing a knock, or ping, the ks picks that up, and the ecu retards timing to compensate, if it runs out of room for compensation, it throws the cel, and runs in retard mode.

__________________
:
93 Runner, 3vze, auto, 4.88 gears, 31" tires, mostly stock, 255k and counting
DD:
94 runner, 3vze, geared 4.56, m/t, 31/10.5/15, only 233k on the clock
Project:
91 p/u, 3vze, m/t, 2" body lift, 4.10 gears, 33's, 235k on the clock.
It's becoming an addiction.

shaeff

You are wrong. The knock sensors are invisible, meaning that you have no idea that they're working if everything is functioning properly. When you get code 52, it has absolutely NOTHING to do with spark knock/detonation/pre-ignition, or vacuum leaks.

Code 52 is an ELECTRICAL problem. The possible trouble areas are:
1) Knock sensor(s)
2) Wiring
3) ECU.

That's it.

__________________
My heatercore replacement writeup with pics.

-'94 Toyota 4X4, 22re, 31X10.5 BFG M/T's, 5 speed, MC rear bumper. (Winter DD/ off road fun)

-'95 BMW M3, modded/suspension, sticky rubber, back road monster (Summer DD)

-86.5 Toyota Supra, too much to list. (Never-ending project)

James64

Hey Sanchez, I'm having the same exact problem. Was it your ECU?