I am getting ready to put my engine harness back on my rebuilt engine along with the rats nest. But probably like most other people here, the harness is nasty and most of the coverings are cracking off. I was just wondering what everyone else was doing about theirs. I heard electrical tape is not the best option. Is this true? Is there any kind of high temp wire loom out there? I would think that that would work alright. The factory stuff just looked like wire loom anyway.

Thanks for the help

 

The best option is buy a new one from Mazdaspeed Motorsports development, $476...

Jeff

 

God, another temptation. I miss the old days when I used to spend money and my car would go faster. Bushings, wires, batteries aren't as sexy as intercoolers, mufflers, ect.

 

AHHHHHHHHHHH!

 

And if we don't want to pay the $500, there is no other alternative?

 

yeah, i removed all unnecessary wiring (solenoids, sensors, stuff from the twins) and got some heat shrink sleeving (it looks like nylon fabric, but it heat shrinks)

it looks awesome, and will only get tighter with engine heat

 

Hmm, that sounds cool, can you get it over the electrical connectors and everything else. Meaning, can you slide it on pretty easy. Also, where do you buy this stuff, how much?

 

yes, mcmaster.com

it's called "heat shrink sleeving"

i got 2" and 3", it fits over the connectors very well

 

When I did my Haltech install on my TII I used DEI "cooltape" to cover the wires. It is an insulative tape that is made of aluminized fiberglass cloth.

Most of the harness I wrapped by using long narrow pieces so there was one seam on the bottom of the wires harness instead of a spiral pattern. Just looked better to me.

I was tempted to re-wire the entire harness w/ SIS type silicone insulated wire since we have some at work, but i was more temped by the thought of getting it running soon.

Lets see if I can find a pic of my "rat's nest"

 

Where do you get that tape, Blue? Expensive or not?

 

I bought it at Summit. It was not cheap, but I bought way more than I needed.

I used the tape, but sleeves/looming are also available.

 

Well I got a friend that can get some Scotch 27 Fiberglass electrical tape. It claims to be good up to 350+ degrees. Not quite sure if I should use it or not but it would be free. Anyone used that stuff for anything with any effects, bad or good.

Thanks

 

the tape might be good to that point, but is the tape guarding the wires from that heat. if your harness is already trashed, just put plastic loom on it. you cant "revive" it with fancy tapes.

take your harness and look for messed up jackets and just plain weak connections. get some wire and replace or repair the wire. if you are soldering (which is a damn good idea), make sure you know what youre doing. if you get a cold solder joint, you wont be doing any better. . . in fact quite the opposite of your goal. old wire is hard to solder on. you gotta get it hot as hell and let the solder bleed into the wires to make them work right. getting it hot turns into getting your hands hot so wear some gloves and the jackets will end up melting as well. get some heatshrink tubing and cover the repair. if the repaired place is bumpy or pointy at all it will damage other wires as they rub. cover sharp edges with some e-tape, then cover the whole thing with whatever you like to make it look clean. me. . . black wire looming is plenty fancy for me.

paul

 

You can also put silicone hose over it, did it with mine, not finished yet.

 

This is my story with regards to the wiring harness:

Background: I bought a parts car 7 years ago. It had a harness but the freaking idiot cut the harness at the firewall. The harness is in excellent shape except for the amputation.

Fastforward to 2003. The original harness in my car is brittle and generally just real shitty. I got the bright idea of cutting this harness at the firewall, i.e., leave just the tail end and then splicing this tail to the body of the spare amputated harness. This will save me $600, at least that's the plan.

So I started prepping the wirings for solder and heat shrink tubing. Turned out that there are about 62 wires total. I figured, why not, only got $600 to lose if I screw up.

Everything went great until I came upon two identical red/silver colored wires on the tail section and on the amputated section. Which wire can be spliced to which one? Do I risk tearing the harness apart to fix on freaking one wire?

Ended up getting a whole new harness from Ray at Malloy for $572. There goes the budget for HID conversion.

May be I'll figure which red/silver wire goes to which red/sivler color wire by testing this brand new harness.
In the mean time, I've got two amputated harnesses sitting around.

One thing that I noted in preppring the harness that the heat damaged wirings have started to oxidize under the insulation and eventually I would be having problems with these wires any way.

 

http://www.designengineering.com/products.html

I also did my harness with this. Kinda looks like somethin from NASA.

 

Harnesses definitely suck. The short answer to the original question is buy a new one. My car was running pretty well until I started smelling fuel. Turned out I had leaky primaries, no big deal. The shop replaced them, and commented that my harness was getting pretty brittle and it was hard to move it around without fearing that stuff was breaking. Well, sure enough, I immediately started having weird problems. The car ran overly rich, smoked and backfired, fouled plugs, and refused to enter closed loop mode. We looked at everything, replaced some sensors that seemed questionable, even replaced the air pump...no luck. Finally decided that the only thing left that could logically be causing this was the harness. We put in a new one and voila...runs like a dream again. So, the moral of the story is...old harnesses suck, and they do so in ways that may not be immediately obvious, i.e. you could end up chasing your tail for a while trying to fix some problem that ends up being the harness you tried to be cheap with.

jds