89 Fuel Injection Harness Removal ? Any Pointers?

[1972C10]

I am about to remove the Fuel injection setup off an 89 C1500W/T Any pointers to make it easier I looked it over today looks like the big bunch of wires go trough the cab an hook the the ecm but there are some wires going towards the drivers side of the truck that plug into the harness im assuming these are for idiot lights etc. I need to get all the nessacary componets since i am getting rid of the shell .

Under the hood it apears that the large bunch of wires coming from the ecu join into a smaller bunch about the size of a quarter that go to the fuse panel I havent taken the loom off the only engine function in the smaller set i see so far is the O/2 and it apears to be going back towards the ecu Do i neeed to unplug this from the fusebox ?
The wipers and some other non engine items are in this set Im sure i will figure it out once i remove the loom and see whats going on

I was plannin on marking certain things with masking tape and a pen.

Im hopin its a straight foward unplug everything type of removal but im prepared to have to solder in some stuff when i reinstall it.


Any suggestions would be greatly apreciated.

[greg0380]

I just did this swap. My advice would be to grab anything you can. Most of the wires go tothe ECM (it should be mounted near the glovebox) are in that harness. There are some important ones that go to the fuseblock (like the fuse and power for the ECM, fuelpump) I would suggest getting the wiring schematic. IT is available online. If you need the link let me know and I'll send it to you. Make sure to grab the vehicle speed sensor, I think it's behind the speedo. I had to buy an aftermarket, it was easy and works good.

[patgizz]

grab everything and sort out later. cut the dash with a sawzall to get to the wires if you have to.

[1972C10]

ive already got a vss but i was told this tbi is standalong i know it worked once without the vss the plug got halfway pulled out the sender on the trans and it still ran great.

But i cant slash the dash the truck a friend wants to build a 4x4 out of the body so i have to remove only what i need and try to leave the rest of the wiring functional.

[greg0380]

Things run alot better with the VSS. Has alot to do with idle, torque conv. lokup, mpg, and keeps the check engine light off and the trouble codes clear. They will work with out one, however.

[1972C10]

Well thats fine I just hope the vss in the dash is the same signal out as the vss on the 89s trans mount sensor Im not going to be able to put the elec sender on my trans because my speedo is cable drive And i imagine the chances of getting a 90 91 suburban or blazer speedo cheap are slim to none.

So im gonna research what signal output my speedometer mounted vss for the cruise in my 85 is compared to the trans mount on the 89


Thanks for the info And i dont have convertor lockup on either truck the 85 has the TH-400 and the 89 Has A Th-375 Basically same trans.

IM going to get the kickdown wire off the 375 and hook it to my 400 since its controlled by computer and TPS And if it dont do right ill hoook up the original kickdown thats mounted on the gas pedal.