Mech pump into efi truck and trans not changing right.

[dryalls]

Hey team,

Since we're all in lock down thought I'd have a look at a few things in my truck.
Firstly it's a 95 bighorn that must have originally have a efi fuel pump given that it has a redundant plug near the injector pump and an ecu. What i want to know is what swnsors and plugs i can do away with, and what i need to fo to get the tranny to change correctly, it's like it's changing up late and I'm not in power mode. Wnd up doing 3k rpm at 100km/h. It seems similar to when i had a TPS playing up in another older bighorn.

I'd love to hear what you guys thinks.

Cheers,

Dan

[Myarmila24311]

That means have you changed the pump or are you still using the efi pump

[Myarmila24311]

If it is changed, the auto gearbox will lose direction to change the gear perfectly. TCU needs input from the ECU to function properly

[Myarmila24311]

There are 3 wires out from ECU to TCU if I am not mistaken. TPS position and torque out. Torque out wires do not know whether data out or trigger only.

[Chchbiggie]

following

[paulthepilot5]

Have you got a TPS in the system still? The earlier transmissions in the 4JH1 TF rodeos seem to function if TPS is kept in the system. Not sure if this is applicable to the ELF but worth looking into.

[Brinky]

I don't know if this will help but in my 2.8 Mu the auto trans was changing late, and jumping down a gear or two at every hill. By turning the TPS on top of the fuel pump back as far as it will go the trans now changes normally and holds the gear up hills. Sooo much better! Good luck.