Underhood wiring

[hammerhead]

Hey guys, most of the wiring underneath the hood, esp the ones running close to the engine have become so brittle that the insulation is starting to crack of. My question is how's the best way to go about replacing these wires. Is it one main harness that goes to all the sensors, or do i have to get separate wires. How difficult is this to do?

THanks for any input..

 

[Boss302]

all the wiring?

 

[hammerhead]

like i said, mostly the wires running anywhere close to the engine, the ones running along side the firewall or fender are all fine.

 

[wingman]

that's the main engine wiring harness, i don't know how much a new one costs but i think there in the neighborhood of $500 from toyota, goes from in back of the engine to the injectors and over to the temp and oil sensors. But if only the insulation is becoming brittle maybe it would pay off to remove the harness (major PITA though) and replace all the insulation with some from autozone.

 

[snotboy]

keep an eye out on here find someone parting a car out and pick the harness up for a good price

 

[IJ.]

I wouldn't put it off too long as it has the potential to burn the car down at worst and at best strand your butt in the middle of nowhere....

 

[hammerhead]

thanks, guys. Will see if i can pick one up.

 

[BosoMKII]

So the insulation around the actual wires or are you talking about the insulation for the entire loom? All the plastic that protects the wires has crumbled off my harness, but the wires themselves are fine. That sound like what you have? If yes, just put new insulation tube around the whole thing like Wingman suggested. If the wires themselves are in bad shape, you could get a new harness from the junk yard.

 

[hammerhead]

Are the harness all the same for the 7mgte, or are they different for the different years?

 

[hammerhead]

And is it true that i could swap an auto ecu and harness into a 5 speed supra?

 

[mkIIIman089]

You could... but why would you want to?

No, not all the wiring harnesses are the same, pre 89 were different from 89+ and 89 was a mish mosh of both.

 

[3p141592654]

I have noticed that the corrugated plastic that Toyota tapes around the loom turns to stone, but the actual wiring insulation seems to hold up better. The connectors are also very fragile, but I have been able to remove all my 16 year old ones without breaking any by being careful and taking the time to examine and understand where to push or pull to release the catches.

 

[hammerhead]

You could... but why would you want to?

Because of availability.

No, not all the wiring harnesses are the same, pre 89 were different from 89+ and 89 was a mish mosh of both.

So basically i need the harness from 87 or 88 model, correct?