Oxygen sensor Molex repair

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Sep 2, 2013
First of all Hello all. This is my first post since joining recently. I am the new owner of 94 fjz80 and have been doing a lot of reading in here. Lots of good info.

My dilemma
The CEL on my LC was on when i bought. It didn't really matter at first because I got it for a smoking deal. The code I got was 28 which is oxygen sensor #2. I replaced both and tried to reset it. I took the efi fuse off and disconnected the batt with no luck. I did notice that it had some corrosion on the terminal and cleaned it up and tried it again. With no success I'm now thinking the connection might be bad. I have searched both here and WWW. with no success. Does anyone on here have experience they can shed to help simplify the process of repairing/cleaning it.

Is 94 OBD 1 or 2?
Autozone or your nearest parts house *MAY* be able to shut off the light.
96 was the first year for OBD2, afaik.

If you still have a code you'll need to troubleshoot according to the repair manual. Did you use genuine parts or aftermarket brand?
Irá a 94 obd1. It is aftermarket and before you say it yes I know Mr. Is superior. I was digging and came across SUMOTOYs' thread on using Bosch ones figured if give it a shot. Heck 60 bucks for both why not? As mentioned in the original thread it does have some corrosion on the plug which I believe is what's causing it not to read appropriately. I was just trying to summons all the electrical gurus on how to disassemble and clean up connector for proper connection.
The connector interlock is pretty simple. There's usually a white interlock that you remove, then the terminals can be released with a dental pick.

It's gonna be a pain to do under the car tho. For sure.
GusMoon: Welcome to Mud. How is the rest of the wiring for the O2 sensors?

The Toy Electrical Wiring Diagram Manual (EWDM) has instructions on how to take the connectors apart. See page 12. The EWDM should be available electronically on this site.

I do not have much else for you. Once you get this code worked out:

I suggest using contact cleaner and emory cloth to clean your electrical contacts generally. Then dielectric grease is your friend for keeping all your newly cleaned electrical connections corrosion free and protected from water.


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Welcome to mud:flipoff2:. I had problems with corrosion on one of my O2 sensors a while back. The terminals on the harness end were so corroded that no amount of cleaning was going to make it work. I ended up getting some replacement terminals from the local Lexus/ Toyota dealer. They keep some pigtails in stk for this type of thing.

Also, be very careful using any dielectric grease as some types will cause silicone to swell, and the seals on these connectors are made of silicone. Ask me how I know...
Toyota OEM Oxygen PN

Can anyone confirm that toyota PN 89465-60110 is still being sold as a kit? I've done some searching online and most places describe it as to it being just one sensor. I'm stumped!



Here's one thread:


Another, see post #3:

Oxygen sensor kit 89465-60110.jpg
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Also check the wiring that goes up and over the tranny on the inside sensor. They run near the EGR down tube and if they've come in contact they could have melted causing a problem.
You can pin out the connector back to the ECM and make sure that connection is intact. While at it, cross check connections to verify that 2 wires are not shorted.

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