I've got a wiring harness that I am going to use as a replacement for what's in the truck now. My truck has the gray remote mounted TFI module and the harness I got has the black remote mounted module.
I see there's only a small amount of wiring between the two but I'm not sure if I should change it. Is there an advantage to using one vs the other? If not I'll just keep the black one on the new harness
The TFI (ICM) has to match the computer. The Black one goes with a CCD Computer and the Gray one does not as it is used with a push start computer.
Also the wiring harness are different. The Gray one has a start wire going to the TFI and the Black one does not. Also the Gray one has a resister going from the coil to the computer to generate the IDM information to the computer where the Black one generates the IDM to the computer.
So with a black one the engine may be harder to start as there is no start wire to make the TFI fire on base timing as the engine is cranked.
To start with in their look-up they only cover 1984-1993.
The TFI module is just an off and on switch operated by the computer with the SPOUT in and operated by the PIP with the SPOUT removed.
The off & on switch is a transistor taking the Ignition Coils primary winding to ground.
The same job the points did years ago.
So there is no way it can improve anything unless they came up with a faster switching transistor or a transistor with a higher current carrying capacity. They may be able to keep the transistor on longer after the PIP or spout signal to get better MPG (longer dwell). But you can get inferior products when you do not go with the OEM item.
I have also heard the after market ICM's fail a lot faster than the OEM modules.
I found a resistor and it is shrink wrapped and has printing on the outside (looks like this came from the factory like this, I am used to seeing the bands). It's clearly labeled as 2.2k ohm and measures 2.187k ohm. Is this going to be ok?