LS Wire Harness Length?

[brian1115]

Does anyone know if a stock ls harness from a truck will be able to mount the computer under the dash? Or do I have to extend it? If so by how much?

Thanks

[mongocanfly]

Should be plenty long..maybe to long unless you shorten it...

[layinrocker65]

The factory harness runs off the top of the intake manifold to the drivers side fender well. I would be willing to but it won’t be long enough without a serious amount of modding to the harness.

[kipps]

Originally Posted by layinrocker65

The factory harness runs off the top of the intake manifold to the drivers side fender well. I would be willing to but it won’t be long enough without a serious amount of modding to the harness.

Agree with this. The fuse box and ECM are mounted on the driver's side inner fender. There's no extra wire to go anywhere else. If you re-engineered the harness, you'd probably find that many of the wires will reach the cab because you're using a different route, but some of them will definitely be too short.

To answer your question about how much to lengthen the wires. If you leave the bulk of the harness as-is, and just turn the main pigtail of wires toward the firewall, I'd guess you need at least two more feet to get the ECM into an out of the way place in the dash. That would be minimum, but I haven't actually measured.

I'm simply putting my fusebox and ECM on the inner fender, where it's supposed to be.