renix aw4 losing tcc lock up again...

[Hellbent]

well......interestingly, i'm definitely not getting anything out of the tcu going down the #3 solenoid wire. now i just have to figure out why.
another strange thing....while i was out driving around checking for voltage on that wire, when i stopped at a light and took off again, the transmission started off in 2nd gear. did it twice in a row-then never did it again. it has never done that the entire time i've owned it.
gonna grab a tcu out of the junkyard tomorrow and see how that goes. they're cheap, and i wanted to go look around anyway.

 

[cruiser54]

Get a TCU from an 88 to 90. Avoid the 87s.

What year is your XJ again?

If it's an 87 or 88 you might wanna grab an 89 or 90 ECU ending in the number 428. More horsepower.....

 

[jeremyj]

I've been having the same issues in my '96. I know it's a different setup than the older models, but I figured I'd chime in anyway. I've thrown all types of money at it and nothing's worked yet. It went away for nine months after replacing all the solenoids, but then came back. I've swapped out the TCU before and it didn't help. I'm hoping your wire-chasing comes up with a new lead for me.

 

[mtbxj87]

I had a shift issue on my 89 a while back. I found a loose fitting terminal in the TCU plug. I pulled each terminal out of the pigtail and re tensioned them.

 

[cruiser54]

I had a shift issue on my 89 a while back. I found a loose fitting terminal in the TCU plug. I pulled each terminal out of the pigtail and re tensioned them.

Not surprised.....

 

[Ecomike]

You like the internals of a TCU?

How did the fuel pump ring tool work?

I am an electronics guy also, father was also a PE-EE, with a computer patent in 1963, I grew up in a house full of electronics, WWII surplus ham radio gear, TVs being torn down and repaired, I did a lot of that back in the 60s and 70s.

Fuel pump project is on hold as the tank is 1/2 to 2/3s full of gas and my helper insists we must drop the tank, which I agree with, and I am not healthy enough yet tackle it my self, and I have never ever dropped a gas tank, I am not crazy about the idea!!!! I have not had a chance to modify the tool yet either. He says the bottom of the trunk above the tank and the mid point flange and the fuel line are all in the way of using tools. We solved the the fuel line issue with your tool, but not the ears for grabbing the ring removal issue or the handles being in the way issue yet. Our last trip to fiddle with it, wasps / nests ran us off. Now the heat and humidity is off the charts for me and my health, and prior weeks everything was flooding here. Feats or famine. Expecting July Snow next LOL. It is parked out doors of my shop in the blazing sun.

 

[Ecomike]

well......interestingly, i'm definitely not getting anything out of the tcu going down the #3 solenoid wire. now i just have to figure out why.
another strange thing....while i was out driving around checking for voltage on that wire, when i stopped at a light and took off again, the transmission started off in 2nd gear. did it twice in a row-then never did it again. it has never done that the entire time i've owned it.
gonna grab a tcu out of the junkyard tomorrow and see how that goes. they're cheap, and i wanted to go look around anyway.

I installed a permanent wire tap on #3 and ran it to a small red LED bulb so I can see when the power was on and off.