Stupid question here.

 

I'm doing the wiring up on my red car ATM and i need a little help with how to wire up the ECU.

 

There are two wires +B1 and +B. where do these get connected to. I assume they are to a relay of some kind.

 

BATT I assume just goes to a constant 12v

 

and FC cuts fuel when the engine stops running and the ignition is on.

 

Any tips where to plug these in?

This sounds like a job for..... SUPER FOOK!! :P

Erm... now to dig up the old wiring diagrams and see what I did... Will get back to you when I actually find these diagrams :P

BATT is constant 12V, usually to somethin like the STOP fuse or something.

 

+B1 and +B are pretty much the same wire, you can join them together. These go to your circuit opening relay, and will get power when your EFI main ralay comes on, ie when IGN on.

 

FC again goes to your circuit opening relay. Basically when the engine is on the ECU earths this, which in turn pulls the relay on for the fuel pump.

hmm OK I think i've got this right

 

ATM i have the +B and +B1 connected to the wires behind the main EFI relay

 

BATT is hooked up easy enough

 

and FC isnt connected yet but it shouldnt need it anyway

 

the car cranks but wont turn over.

 

There are also a shitload of leftover plugs which have me worried.

Do you know why it doesn't turn over yet? Fuel? Spark? Something else? EFI cars are a pain to diagnose...

 

How are your fuel pumps turned on and off if you're not using FC? I take it you don't have a proper circuit opening relay?

 

You'll normally have a few plugs leftover, I know I took out a few before the loom went in the car, and I still have about 2 that aren't plugged to anything. What have/haven't you plugged in?

can't say for sure but i thinks its something to do with the wiring

The engine was literally pulled out of the donor car and dropped into mine on the same day.

 

+b1 and +b are getting 12v when the ignition is on. the fuel pumps are just wired to the accesories as well.

 

I'm a little unsure but would it be the fact its connected to the efi relay and not the curcuit open relay thats the problem?

 

How do you check if the injectors are injecting fuel or not??? I can hear fuel being pumped through the lines.

i'm no expert on efi, but i'm pretty sure you can use a dwell meter (dwell/tachometer) to see the injectors cycling.

Okay, past the limit of my knowledge :P

 

I doubt the lack of circuit opening relay will stop it working, I've heard of people wiring up their cars with just normal relays before. Shouldn't be a problem to have pump wired to accessory, just dangerous (if you have a prang pumps will keep pumping)

 

Umm... not sure :P

If i knew the physical location of the cuircuit open relay it would be a lot easier.

 

We have determined it is getting spark and theres fuel getting to the rail. I just don't think the injectors are firing

yep just did a search and it appears you can use a "dwell meter" to measure injector pulse width. google it.

OK now that i've had a think about it i realised the ecu was getting power but nothing was telling it to fire ze missiles.

 

I'm guessing i take the STA and stick it on the start switch of the ignition barrel

this should cause it to start but then it needs a signal to stay on. where would i take this from??? and which ecu plug does it go to???

Umm... Okay, lets see if I actually remember anything useful.

 

+B1, +B = IGN Power

FC = Circuit opening relay (for fuel pump)

KNK = knock sensor (under intake manifold)

VCC, VTA, IDL, E2 = TPS

OX = oxygen sensor (on exhaust manifold)

V-ISC = you don't need this

STA = STA Power

#10 = injectors 1, 3

#20 = injectors 2, 4

E1, E01, E02 = Earth

IGF, IGT = Ignitor

G1, G2, N2 = Distributor

A/C = you don't need this

W = check engine light

SPD = you don't need this

ELS2 = you don't need this

BATT = Constant power

 

Can't remember the rest.

Edited August 4, 200422 yr by demuire

Know I may be a bit late but check out the mr2 site for a wiring diagram

 

Your circuit opening relay usually mounts underneath your computer

 

Once you have a relevant wiring diagram start from scratch and check all of your connections.

 

and please solder all joins , not twist them together like somebody i once knew did who had a number of intermittent problems.(wonder why)

Also, make sure you have good earths. It's amazing what strange things can happen when you miss an earth :dance: