Wiring engine from scratch...

[allmtr]

So I bought a bare 4age motor out of a 1990 Seca and it is all mounted up and now I've come to running it. Would I be better to run an aftermarket computer (probably Microtech) or is it within reason to wire up the factory computer? There is no factory wiring in the car at all so it really is starting from scratch....

BTW I searched but it is such a general topic :/

[mrshin]

If you're planning to leave the motor standard and are happy with the way they go normally, then use the factory gear. If you're planning to do some stuff to the engine (cams, head, etc.) then use something aftermarket.

[sideshow]

i have 100kw looms and ecus if you need to go std

to buy mictrotech its about 1000
wiring if you cant do it is around 600
tune is around 300

if u go std
100kw ecu is up to 150
and a loom is 100
wiring is still aorund 600
you might find ecu and loom cheaper if you know someone or not in a hurry

[allmtr]

When you say you have looms is that to run the motor stand alone or just a standard loom. Even if I go microtech Im still probably gonna need a loom for the connectors...
I know I can wire a microtech as I had one on my Civic and there was only about 6 wires but I aint as confident with a factory loom....

[sideshow]

6 wires my ass heheh

last time i checked there was about 20

anyway the loom is a std 100kw fwd loom so if its goin into the correct car it will plug in

if its goin into a car that didnt have a 4age then the loom needs to be modified

connectors are easy to find anyway

[allmtr]

Hehehe well it has been a couple of years so it probably is about 20 wires but hell easy. The motor has some dizzy bits missing so I might bite the bullet and get a Microtech :/
At least that way the loom is labeled

[sideshow]

just dont by a 2nd hand one

[The Witzl]

buying a microtech wont fix the problem that your dissy (or parts thereof) are missing.

Stock computer will do more than enough for you, unless you are planning any mods like Mr Shin mentioned.

Do you have a stock ECU?
What car have you put the 4AGE into?
Do you have ANY wiring loom at all?

i might have some parts you need

[mrshin]

When wiring up a fairly simple engine, I really don't see how the factory box is any harder than something else. *This colour* wire goes from *here* on engine to *here* on ECU/fusebox/etc. When you're done, you should be able to turn the key and make neighbour-upsetting noises.

[infotechplus]

When wiring up a fairly simple engine, I really don't see how the factory box is any harder than something else. *This colour* wire goes from *here* on engine to *here* on ECU/fusebox/etc. When you're done, you should be able to turn the key and make neighbour-upsetting noises.

Gee, I wish it was that easy!

Peter

[mrshin]

You just have to know WHAT to string the wires between to get everything working as intended

[bansheebuzz]

id like to add from a professionals point of view. Its one thing to get it to work, its another to make it neat, tidy and reliable

[thechuckster]

engine loom is actually quite simple (having done it for the 18RTE) - integrating it into the chassis loom and charging systems is quite difficult - given that generation of EFI car seems to do things a bit differently.

If you get a haltech it comes with a loom for ecu out to xxx points on the engine. You supply the connectors for various items and join them up to the loom as required.

best hint eva: wire colours are useless ... you have to know what each particular wire does and how it is connected. If you just rely on wire colours, then you may as well be doodling join-the-dots artwork.

[mrshin]

If at all unsure, use the continuity function on your mulletmeter - it's amazing how handy these things are for all kinds of things...

Also make sure you have a piece of paper and write stuff down as you find it - it's amazing how quickly the mind can come up with all manner of weird things when it isn't written down. Taking a little extra time to actually draw proper little pictures for everything when you don't already have a diagram is very handy too, not just for when you're doing it, but you'll also thank yourself greatly if/when something goes wrong.

Another thing, get familiar with the abreviations used for both wire colours and pinouts.

[oldcorollas]

wiring is actually simple, because it is basically just logic... the wire either goes there or not

once you have wiring diagram, you can make your own loom easily, however as Banshee said, making it work and making it neat are far apart...

i designed integrated wiring for my poor little car and it looked great on paper, but i didnt put in enough effort to make it look neat
if you can't be arsed buying different coloured wire, you can use rings of different coloured heatshrink tubing to identify wires at each end and at certain points....
heatshrink is more expensive than wire tho, so coloured wire aint that bad.

i'm just abotu to start designing next modular wiring system..... but this time will also have a vehicle placement strategy

so basically.. wiring is simple, you just need to kno wwhat connects to what (and what else).
making it simple can make the looms bigger and less neat, but more reliable in terms of things being standalone.
if you want to demysify EFI loom and wiring and connections, read the MS MegaManual...