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Oh boy, fun. I labeled everything, or so I thought. I have the original wire harness from the rx7, plus the engine to match, the factory wire diagram (all 118 pages). I placed the battery, and the main fuse box in the car last night, stripped all the tape off the loom, and had time to chase 1 wire from the fuse box out to the plug where it ends. It just so happened that this 1 plug isnt marked (Lucky me). So 2.5 hours worth of work and I'm still not sure where the plug goes too. I just want to get rid of all the wires that i don't need, like sunroof, power windows, power locks, AC etc....

I took some pics with my cell, I'll try and post them up later.

wHEN i STARTED STRIPPNG (damn caps lock) my mazda b2300 i labeled All my wires and what plugs where. I can't believe HOW many wires a pickup truck has. I just want the bare bones locost but everything has wires to it. Roll up windows and it has manual mirrors so I can't understand WHY there are 10 different wires going into the doors.

Sure engine management, turn signals, lights, brake light....but what else should there be?

I want to reduce it to bare needs but I will have to Megasquirt & Megajolt it. Piled together it would be an ugly plate of spagetti.

Has there been any butchering done by previous owners? That can make life REAL fun! My last teardown found three live 12volt wires just hanging under the dash, most probably from an extra brake unit. Two were red, one black, all three different gauges. Also had two 3/4" bundles of wires leading from the engine compartment through the cab, and to the back end, also probably for extra brake systems. One was live, the other only had the positive leads disconnected. Extra speaker wires were running under the rubber floor mat to behind the bench seat. Frayed and useless, of course. I threw out about half of the wiring I started with - all of which was owner-added, none labled, none spliced correctly/safely, and little of it a color which made sense (Hey, let's splice in a red wire for the ground! ). Some people should be taken outside for regular beatings....

I built a Megasquirt (also used the relay box) for an old 86 GTI that I swapped a turboed 2.0liter engine from a 98 Jetta into. It really was suprisingly clean. Only a few wires to the sensors, injectors, etc. I don't know about Magajolt though, that's uncharted territory for me.

More than likely, the wires were there for the upgrade options. A lot of vehicles that come with option have the wire in place in case the person opts for the options. A pain in the rear none the less.

2004 Mazda B2300 2.3l Duratec has distriberator-less ignition...fuel injecttion...ABS...AC power steering.

It also has had of the wirring cut out on the driver side front by the brake system, headlights, and turn signals...sigh. It will haunt me later I am sure.

Wow, that stinks. I know people that have run Megasquirt as a piggyback fuel computer in conjuntion with their DIS car's computer but I that wouldn't accomplish much for you. Maybe a full standalone system is in your future.

Manufactures build cars with wiring in them for any extra feature (power locks, windows, mirrors etc...) even if they dont have them on the car. It's cheaper to build every car with the same wire harness than build each wire harness specific to the car.

My engine harness has been slightly cut up (my fault) but it has given me a great place to start on. I started to trace wires from the ecu to their plugs around the engine. Ive located 14 wires so far, and created 1 complete loom, wired up the injectors, placed the main fuse block, and decided that there are still 15,000,000,000 wires left to go through so i need to find out which ones I don't need.

Ive also come to the realisation that japanese electrical engineers design their wire diagrams to show their prowess at making thing as complicated as possible. I keep finding more pages that say refer to page 15-67 which is in a completely different part of the manual, so now my 118 page wire diagram has grown to a little over 280 pages.

Here are the wires from my engine bay...

Oh my. Consider this as earning a degree in automotive electrical systems!

I don't feel so bad now. Mine's reasonably simple compared to that. I used to have an old Triumph Spitfire - there was only about 4 fuses on that car - very simple (just don't let the smoke out!) except for the horn wiring which was mind bogglingly horrible.

That is more wires than I plan on using. From studying the wire diagrams I expect to have about 70-80 around the engine, another 40 or 50 in the dash, 20 to the rear, and another 10 to the front. I'm guessing that I'm only going to need about 150 wires around the car for the engine, lights dash, and fuel system. I do plan on adding a radio, but that will be wired in later. I am going to leave the harness radio ready, but I am not going to install it yet.

The radio has only 3 wires going to it from the electrical system, +(ignition acc), +(constant), and ground. The rest of the the radio's wires (speakers and antenna) will be added later. I would like to locate 2 speakers under the dash, and 2 behind the seats, not that you will be able to understand anything that comes out.

Yup this is my 3rd attempt at making a hood, I made a really bad attempt with fiberglass a while ago, trying to copy the stalker where the whole front flips up (nose and hood), that was 2 years ago, and I have practiced with fiberglass much since then.

Attempt #2 is my ill fitted alluminum attempt. It never fit right, the corners were off, and I cut it too short

This is attempt #3, I am using some really thin aluminum as a mold, layed the fiberglass over it (6 layers), and I'll let the pics speak for themselfs

Looks like some sanding, finishing, and painting and you are all set. You might want to adjust that toe angle though.

[quote="derf"]Oh boy, fun. I labeled everything

I had the same intention to use the original wire harness from my donor but after about 18 to 20 hours of tracing and pulling wires out of the harness, I realized that it would be much easier to just make my harness.

I think it will probably be less time if you just use the engine bay harness to the ECU and make the rest of harness.

I would draw up the wiring harness first. I copied the service manual and then enlarger it so you could easily read it then cut and past the items that you actually need on a large sheet of paper, 30 x 25 inches, then draw in the wire with indicated color codes. The design time was only about 6 hours, but do it in pencil if you have to change any thing or your wire color codes or add any thing.

Rule number one save all wires and connectors, from the donor, you'll only use a 1/3 of them but it will make for a much better looking job.
good luck on the wiring Dave W