1990 V6 Code 52 and 53 (Knock sensor)

[The_Joe]

Hey ya'll

My sister has a 1990 4runner with the V6 engine, 5 speed, and the check engine light is on.

Background: I tried hooking it up to the code reader at O'reilly's, couldn't get any communication from the diagnostic port. We used a paper clip to get the check engine light to blink and tell us the code, result was code 52 and 53.

Purchased the new knock sensor and its bit of wiring harness. I had read about relocating it to the engine hook, made logical sense to me. I found the original wires were severed, so I thought for sure I was on the right track! Drilled the hole, mounted the sensor, plugged it all in... and still get the check engine light every time she shifts to second gear.

Same codes, no difference. What have I missed?

I really dont want to take this old run down rig apart far enough to put the knock sensor back in its correct place, especially given that I have no reason to believe it will make any difference at this time.

One photo is of the knock sensor mounted to the engine hook, the other is a photo of the Diagnostic port, which is all nasty looking.

 

[wshiverick]

Not totally sure on these, but most knock sensors ground where they sit against the engine, did you clean the area well and bolt it tight?

 

[The_Joe]

I will double check the ground, but I know the sensor has a good connection to the hook.

Are there other suggestions on this issue?

 

[Scalded_Dawg]

Did you pull the EFI fuse for a minute and then re-install to clear & reset the CEL?

 

[The_Joe]

Did you pull the EFI fuse for a minute and then re-install to clear & reset the CEL?

The battery was unplugged for the duration of me working on the car, that should accomplish the same thing right?

I will unplug the fuse and see if that helps. Thank you.

 

[Scalded_Dawg]

The battery was unplugged for the duration of me working on the car, that should accomplish the same thing right?

I will unplug the fuse and see if that helps. Thank you.

To be honest, I'm not sure if simply disconnecting the battery will do the same thing... maybe so.
I am sure that the FSM says to pull the EFI fuse, in the fuse box next to that nasty diagnostic port, for at least 30 seconds to clear/reset the CEL.
It may be that the ECU still needs power, with the lack of power thru the EFI fuse, to signal a clear/reset action.

Worth a try either way... easy stuff.

 

[The_Joe]

To be honest, I'm not sure if simply disconnecting the battery will do the same thing... maybe so.
I am sure that the FSM says to pull the EFI fuse, in the fuse box next to that nasty diagnostic port, for at least 30 seconds to clear/reset the CEL.
It may be that the ECU still needs power, with the lack of power thru the EFI fuse, to signal a clear/reset action.

Worth a try either way... easy stuff.

Tried that tonight, check engine light remains as soon as is shifted to second. I will have to use a paperclip and see if it's the same code later.