DRACO A5OG

So I was asked by a member ( a pro-wrench ) to post a pic of the repair I made to correct the re-curring P3025 even after all known repairs were made.

Some of you may know the story but here it is just for the new guys.

I was working on the transmission, required me to drop the trans and hold the engine up. DING DING DING, you should always do this properly. I lost my chains so I sued nylon straps, doh

So after the transmission repair, I hooked everything up and 100 miles later CEL, WTF?

The dreaded P3025, Ah poop. Okay, went to the junk yard and found two new old sensors off of a dry engine, went to Oriely's got a life time guaranteed Harness and Toyota Bypass hose.

Glad I did this because harness was toast. It crumbled in my hands on both ends. The old sensors tested fine per manual but I swapped with better conditioned (visual and resistance tested only) new old sensors, didn't hurt to do it since I have her apart. By pass was toast too. Man it gets hot there.

All back together, all seemed fine then CEL, WTF?

Re-checked everything. All good but did notice the aftermarket connector was not fully seated because it's connector was fatter than the OEM, used di-electric grease and snapped right in. CEL reset.

2 days later CEL, oh come on!

I was looking for an ECU, then had a brain fart. Line 3 above. What if the harness on the ECU side was compromised due to the sloppy engine hanging I did???

Off to the junkyard, looked for a pliable, not so brittle Harness coming out of the ECU side. Cut as far back as possible. Brought it home upon splicing. I noticed the original wire was exposed with green/black corrosion. DING DING DING. The harness pull was the final straw that did it in but it appeared to be on it's way out due to the corrosion making a weak signal and throwing the false readings.

Carefully spliced the new old ECU side harness on paying close attention to the insulated signal wire ( most important ) liken to an oxygen sensor wire. I also added heat shrink and a shroud with electrical tape to protect it further against heat and oil.

1000+ miles later no CEL FIXED.

Here is the pic:

DRACO A5OG

Here are the ECU side harness connector in question:

The one on the right is my old corroded one ( and this was after I tried to clean it ):



Left is an additional spare I found, most if not all the inner connectors were all yellowed and corroded, this and the one I have on the car were still OEM white with little to no corrosion.



The red clad wire is the one I was very careful with when splicing.