Topic: need Knock Sensoer help

[5150crawler]

Bought a 93 v6 extra cab with a new motor, to replace my 91 v6 extra cab. I know the 3.slow is crap but the price was good, I thought! Anyways got a CEL code 52, knock sensor. Pulled the intakes and replaced the sensor and the pigtail for the harness. put it all back together started it up, and CEL code 52 still there. where do I go now, besides a new motor?

[bad luck]

did you reset your computer before you started it

[lucky7]

What he said ?

[5150crawler [OP]]

Yes. I had the battery disconected the whole time. Truck also has a bad drain onthe battery so i keep it disconnected.

[5150crawler [OP]]

can anyone help me? Im in a bit of a jam, one truck is dying and the other wont come alive..
 

[BLACKDOG]

When you put it all back together, did you make sure the wires were in the little groove on the head, so they don't get pinched by the intake?  Mine had a problem staying in there, and snuck out, sandwiching themselves in the seal, sneaky devils, and made my truck throw that code until I figured it out.

[Snowtoy]

Was the KS and wire new?  If they are, then you could have a short/tear in the lines somewhere in the harness(from the P.O's rebuild), or it is pinched like Blackdog mentioned.  It could also be the ecu.  Does the CEl come on immediately or once you get above 2200 rpms?

The battery drain could be from a bad ground wire.  I had an engine ground wire completely dissolve its sheeting and burn through the surrounding wires in my '91 22re(the ground wire from the alt).  The short that was being caused wasn't enough to blow a fuse/link, just enough to drain the battery down.

[5150crawler [OP]]

thanks for the replies! the KS is new the wire was used but was in near perfect condition. Its not the ECU since I swapped it with the one out of my '91, and got the same code. The CEL oinly comes on after 2000 rpm.
The battery drain i will start tracing out after I fix the knock sensor problem. I just got the truck moved to my house, it was 3 1/2 hours away.

[Snowtoy]

With the CEL for the KS coming on above 2k rpms, the ecu isn't getting a signal from the KS. since the KS is new, the wire is likely bad.  I know it is like new, but the amount of heat that it is exposed to there between the heads will make the wire brittle very fast.  Any amount of movement can crack/break the wire and reduce the signal strength.  KS wire is a very finicky foe, w/o a perfect setting it wont work, you can't even splice two pieces together, the shielding and wire have to be one continuous piece.  I know it is a bit of a PITA to have to remove the intake manifold again, but until you replace the wire w/a new one, you can't rule it out.  The KS should be fine, but if you wanted you could pull it and have the dealership check it out, go to the parts counter, they will likely have a tech check it for free.

[BLACKDOG]

With the CEL for the KS coming on above 2k rpms, the ecu isn't getting a signal from the KS. since the KS is new, the wire is likely bad.  I know it is like new, but the amount of heat that it is exposed to there between the heads will make the wire brittle very fast.  Any amount of movement can crack/break the wire and reduce the signal strength.  KS wire is a very finicky foe, w/o a perfect setting it wont work, you can't even splice two pieces together, the shielding and wire have to be one continuous piece.  I know it is a bit of a PITA to have to remove the intake manifold again, but until you replace the wire w/a new one, you can't rule it out.  The KS should be fine, but if you wanted you could pull it and have the dealership check it out, go to the parts counter, they will likely have a tech check it for free.

[5150crawler [OP]]

thanks Blackdog. I was kind of leaning towards that. Do you know where I can get that shielded wire?

[Snowtoy]

You can get the KS wire at the dealership or import specialty parts store, the local chain store isn't going to have the wire(or at least they didn't used to) You can also try some of the online parts stores one of the online Toyota parts suppliers.  If you don't have a local dealer that has discount day(my local one has a 25% off Wed. evening sale each week), email Butler Toyota here tparts@butlerwarehouse.com.  Their prices were reasonable when I rebuilt my 3.0 a few years ago, they actually beat my local dealers discount.

[5150crawler [OP]]

thanks snowtoy!