EA82T wont start

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 2:49 pm

just converted my 85 touring wagon to ea82t

its a 3plug ecu motor, but it wont start...
im getting spark to the plugs but it just wont fire...doesnt even want to fire...just turns over....

any idea's?

everything is pluged in?

cheers

wrx_nut

MUDRAT · Post by **MUDRAT** » Sun Jul 02, 2006 3:26 pm

Got fuel?

Craigus · Post by **Craigus** » Sun Jul 02, 2006 3:28 pm

Is the fuel pump running?

Have you got the shielded wire from the ECU connected to the distributor side of the coil? Without that, the ECU can't work out engine rotation and won't fire the injectors.

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 3:57 pm

fuel pump is pulseing when the ignition is on...when you turn the key to start it pumps constantly.....

cragius...that shielded wire from the ecu.... are you talking about where it plugs onto 4 terminals under the dizzy cap? and then joins to the coil?

if so they are on but not sure if its the right order?

cheers

Craigus · Post by **Craigus** » Sun Jul 02, 2006 4:05 pm

cragius...that shielded wire from the ecu.... are you talking about where it plugs onto 4 terminals under the dizzy cap?

No; that wiring is for the seperate knock control module - do you have that ?

The shielded wire I'm talking about connects onto the distributor side of the coil (it has a round screw lug, the wire sheath is grey in colour) and goes back to the ECU. Unless the ECU sees this signal, it has no way to tell that the engine is turning anf at what point it is in rotation.

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 4:21 pm

yes i have that and is connected (that goes under the dizzy cap)

on my coil there are 2 wires on each terminal

the 2x yellow wires with the grey cap are on the negitive side of coil

and the 2x black wires with red cap are on the positive side of the coil

is that any help?

Craigus · Post by **Craigus** » Sun Jul 02, 2006 4:30 pm

Well, are you sure the one I'm talking about is present and connected - it should connect to the negative side of the coil. I'm not sure what you mean by "(that goes under the dizzy cap)".

It doesn't sound to me as if you do have it (apologies if I'm wrong here), and the engine cannot run without it.

It's pin 21 ("IG Pulse") on the ECU: highlighted in red:

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 4:52 pm

ive taken pictures of the lot

that there is the knock sensor? and earthed to the intake

these are the wires that connect to the 4 terminals under the dizzy cap

thats my coil.... 2 yellow wires on negitive 2 black on positive

plug into loom...coil...knock sensor and unknown wire??

that help?

thanks

Craigus · Post by **Craigus** » Sun Jul 02, 2006 5:24 pm

Hmmm. Can't tell just from the picures. One of the yellow wires could simply be the tacho connection, and one must go to the distributor or you wouldn't be getting spark. I don't think you've got the "IG Pulse" connection.

I'll post the pinout of the ECU (have to get out of Linux - long story) and you can check with a multimeter if it's connected or not.

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 5:31 pm

ok....thanks for that cragius

the only other thing i can think of is is the distributer in the right spot?

anyone else think of something else?

thanks

wrx_nut

Craigus · Post by **Craigus** » Sun Jul 02, 2006 5:34 pm

Well, the timing has to be set correctly as well of course. Here's the ECU pinout:

Do you have a wire that comes from the ECU loom and connects to the coil?

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 5:34 pm

when u mean ignition pulse.....i put the test light on a few plugs around the motor..(tempreture sender and a few other plugs) and they were getting power in a pulse..which was when the fuel pump comes on and off...

is that what you mean?

im new to this so sorry if they are stupid questions...

Craigus · Post by **Craigus** » Sun Jul 02, 2006 5:44 pm

The ECU has to know the rotation state of the motor to know when to fire the injectors. With the 3 plug ECU system, there is no crank angle sensor, so the only way the ECU knows what the engine is doing is by looking at the ignition pulses on the negative terminal of the coil. If it can't see that signal, it won't fire the injectors and the engine will not run.

That is what I'm talking about - you must have that shielded wire connected (the one highlighted in red above) from pin21 on the ECU to the negative side of the coil. I don't think you've got it connected. Is there a grey (or any other colour) thick-ish shielded wire coming out of the ECU loom with a round screw connector on it?

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 5:58 pm

i havent seen a grey thickish wire with a loop on it near the coil....
the only wires i know of is the 2 on each +tve and -tve terminals on the coil...

sounds like i am missing that becuase it doesnt sound like the injectors are firing any fuel to the cylenders....there is power to them constantly????

Craigus · Post by **Craigus** » Sun Jul 02, 2006 6:01 pm

i havent seen a grey thickish wire with a loop on it near the coil....

Was the car MPFI before the conversion?

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 6:07 pm

no it was carby
the other thing i have noticed is next to the intake there is a plug that doesnt have anything to plug into it....

thats the one just next to the left of the air-con outlets

cheers

Craigus · Post by **Craigus** » Sun Jul 02, 2006 6:12 pm

no it was carby

Well, then that wire won't be there unless you put it there ...
Where did the ECU loom that you are using come from ? Does it have any spare wires? Where are you picking up ECU power from?

the other thing i have noticed is next to the intake there is a plug that doesnt have anything to plug into it....

I think you have the 4 plug ECU style throttle position sensor, which should be OK, as you don't need the throttle potentiometer connected.

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 6:20 pm

i got the 3plug ECU loom and motor from steve@risingsun
its out of an rx 86/87.....ecu power is from the brown fusable link box next to the battery...

havent seen any spare wires...should there be?

Gannon · Post by **Gannon** » Sun Jul 02, 2006 6:29 pm

Pour a little fuel down the throat and see if it will start.

It does look like a 87+ throttlebody.
They have a different setup as far as potentiometer and throttle switch goes.

I suggest pouring fuel down the throat to rule out a fuel problem for starters

wrx_nut · Post by **wrx_nut** » Sun Jul 02, 2006 6:32 pm

will putting fuel down the guts of it damage it at all?