Wire Identification Help (1 Viewer)

Toofless916 · 2025-08-17T12:50:25-0600

Anyone have any idea what the solid yellow line goes to in the wireloom beside the EGR pipe? 94 FZJ80. The wire touching the nut that looks damaged.

When it's in idle, if i move the harness, the engine starts to sputter kind of like a misfire. It doesn't matter if the harness is touching the EGR pipe either. I wrapped the harness and the pipe and it still does it.

145236 · 2025-08-17T17:32:26-0600

My thinking is that it doesn't matter what it goes to, it's a wire with a problem, so fix it.

mudgudgeon · 2025-08-17T19:36:18-0600

Looking at the state of the insulation in those pics, may not be the only one with an issue

Toofless916 · 2025-08-17T19:51:18-0600

mudgudgeon said:
Looking at the state of the insulation in those pics, may not be the only one with an issue

Yup. Looks like the black and yellow is in rough shape, but wire isn't exposed.

Kernal · 2025-08-17T20:11:49-0600

@jonheld might have something to add

A burned (heat damaged) engine harness has been discussed in the past, the main engine harness bundle on the firewall near the EGR droops (often due to a broken harness clamp) then it gets too close to the hot EGR pipe. Add inadequate original harness insulation and the wires inside the bundle melt and start to short/arc.

After inspecting all the wires and repairing them others before you have re-wrapped the bundle (with something like TESA tape) followed by good heat insulation/reflective wrap or sleeve, even a custom heat shield, then hang the harness so it won't droop back down onto the hot pipe.

FWIW I put a split Velcro closure aluminized fiberglass heat sleeve over both the engine harness near the EGR valve/pipe and over the hot EGR pipe itself (can't find that photo)

Here's one thread:

Heat wrap: EGR tube, harness or both - https://forum.ih8mud.com/threads/heat-wrap-egr-tube-harness-or-both.818170/

Here's some photos: