problem: engine won't fire

[ChaosAD]

Just read the first post properly. seems like the ecu just isnt firing the injectors.
Again check every plug, maybe the ecu isnt getting the right signal from the dizzy telling it when to inject fuel.
Do you have the right ecu?

Might pay to post a few links to your other threads so we can see what loom etc your using.

Matt dunn> will the import 4ages spark if the ecu isnt getting power?

It will probably be something simple

[l1ttle_d3vil]

It could be that the only fuel the motor is getting is through the cold start injector (which is mounted on the plenum chamber).
If there isnt 12v then check the 'inj' fuse mounted on the airbox.
Also, there should be a whole lot of solenoids mounted on the ecu end of the engine loom.

to start with, my wiring is pretty much exactly like this. just a few of the colours are a bit different to what these people say but the ECU pin-outs are all accurate.
http://www.club4ag.com/faq%20and%20tech ... 04A-GE.htm

Would it take 6 - 8 seconds of turning the engine over before that fuel from the cold start injector explodes and backfires like that though? Or would that fuel be gone by then?

I don't have an 'inj' fuse, i dont even have an airbox. only fuses ive got is for the 3K/ke35 wiring. i also dont have any solenoids. only stuff ive got on the ECU end of the loom is a yellow 3-deep plug with stuff like ECU power/shared with injectors (white wire), cold start injector (spliced off the STA signal of the ECU) etc. i have connected the appropriate wires off this plug to the particular power sources they need to go to etc (as far as i know).

all of my wiring is standard as far as I can see, with everything plugged into the normal places (injector plugs into injectors, dizzy into dizzy and ignitor to ignitor etc etc). the only stuff ive "added" to the loom is the EFI main relay which i got from another 4age and wired it up to mine. am i supposed to have more relays than this 1?

i just had a look at the wiring of the yellow 3-pin dizzy plug. on the engine loom, the bottom wire is white which matches up to the wire on the other side of the plug (going into the dizzy).
the top left wire on the loom is red, but on the other side of the plug its a blue wire going into the dizzy. for the top right wire, its black on the loom and red on the other side of the plug. is this correct? it doesn't look like the wires have been cut at all on the engine loom. is it possible that i have the wrong distributor and the wires are mixed up - therefore sending the wrong signals to the ECU/injectors?

[ee904age]

If your loom is complete it WILL have an INJ fuse, it will be 10A (I think) inside a yellow plug with a black cap on it. It uses an adaptor type thing to convert from a normal two pin plug to a fuse holder.

Ill check what the plug looks like without the adaptor as it may have been taken out at some stage, in which case it could be one of the 'plugs to nowhere' in the pics from your 1st thead.

Cheers
Shay

[ee904age]

Taken from the 1st thread

that yellow plug is not for the ignitor - it is for the air/con or something like you said.
i found the right plug for the ignitor/coil on another loom and have traced the four wires all the way back - two go to the ECU, one to a yellow plug with a fuse on it (duno what its for), and the other one goes to the yellow plug in the bottom of this pic.

Where exactly was this plug with the fuse. Sounds like the one you're after to me.

[l1ttle_d3vil]

If your loom is complete it WILL have an INJ fuse, it will be 10A (I think) inside a yellow plug with a black cap on it. It uses an adaptor type thing to convert from a normal two pin plug to a fuse holder.

Ill check what the plug looks like without the adaptor as it may have been taken out at some stage, in which case it could be one of the 'plugs to nowhere' in the pics from your 1st thead.

Cheers
Shay

when i got the injector fuse and adaptor off another loom it came off a green 2-pin plug from memory. ive got a spare yellow plug on my ae86 loom and i don't know what its for - is this likely to be the same one? its the #1 plug in this pic. should i just plug the adaptor and fuse straight into this plug?

[matt dunn]

Are there any other marks on the cam pulleys? The gears on the silvertop I pulled to bits had 2 marks on the pulleys, one of each lined up as you've put and the other 2 lined up with themselves where the pulleys are closest to each other, much like Subaru timing marks do.

No. the 16v's only have the one set of marks.

Do you have the right ecu?

There are different ecu's, but as long as it says 4AG not 4AGZ and it plugs in it will make it run.

Matt dunn> will the import 4ages spark if the ecu isnt getting power?

no. no power to to ecu means no spark,
but,
the earth that i referred to earlier are the main power earths which are basically the earth for the injectors.
the rest of the ecu run on different earth wiring.

matt

[ChaosAD]

If the colours are the same as my ae82 fxgt then the feed wire for the ignition is black/orange then it goes through the inj fuse and changes colour to white then goes to the ecu and injectors.
I have a spare loom that I have been untaping to find where every wire goes, most of the ground wires join together in the loom.

I can check the wires on my loom for you if need be.

I thought the red/blacktop ecu was different as it has a different dizzy.
Diddnt you have problems with the plugs not fitting the ecu?

Some of the plugs will just be check connectors for diagnostics etc.

[l1ttle_d3vil]

MY ENGINE GOES!!!!!!!

im stoaked, i swapped a couple of the wires around on the distributor and it fired up and idles mint as. thanks for everyones help.

***free box of piss for everyone who helped out when im in their area next ***

[l1ttle_d3vil]

ok, i take my word back - it doesnt idle "mint"

it did to start with, now im not sure what the problem. it'll fire up and rev sometimes but then die out. to start with it'd start up and idle no problem, but if you gave it some gas it'd die out. now it won't even start up and idle properly.
what degree is the timing supposed to be set at? im wondering now whether it is a fuel starvation problem or whether it just needs to be started and revved to get all the shit out of it as i dont know how long its been since it was running.

[ee904age]

Good news man, great feeling isnt it!

I would get it warmed up an keep it running for a while before worrying too much about idle etc.

Go over it with a fine tooth comb checking for leaks of any kind etc.

[l1ttle_d3vil]

I would get it warmed up an keep it running for a while before worrying too much about idle etc.

thats the thing though, i cant even get it started now to rev it. maybe if i cross my fingers the right way it will though

but yes it was a good feeling...now im back to "what next"

ill go check for any leaks now, i presume for it to start up and run like it did before the injectors are working. it seems now that its back to how it was before though, except sometimes it tries a bit harder to fire. otherwise it just backfires out the manifold. but if i spray engine start up the manifold while turning it over it'll try to fire, then if i stop spraying it it'll stop firing. otherwise it'll pretty much start without engine start.

[ChaosAD]

Wicked, you would have learnt a fair bit from it too.
so it was the dizzy signal aye.

Give your engine a tune up, set tps, gap the plugs, bridge the 'check connector' and set the base timing to 10 degrees and check for fault codes.
If the timing was set with the wires to the dizzy wrong then the timing is probably a bit off

[l1ttle_d3vil]

yep, learnt a sh*tload for sure. from bogging/panelbeating to sanding, painting, welding, engineering, auto electrical, to labelling what bolts come from where

ive just run a compression test and its around 170 - 180psi on all four cylinders, also tested the fuel pressure which is 60PSI. this is a bit low isn't it? im running a pump off a VL commodore.

[ee904age]

Your fuel pressure is sweet, mine runs about 60psi with the engine off and 40psi at idle

[l1ttle_d3vil]

okaay....what else is wrong then?
it slowly seems to have got worse and worse (firing/starting less and less) since it started this afternoon so i thought maybe the answer is something simple...like not enough fuel (seeing as i dont have a surge tank). so i stuck a few more litres in but still no luck...

[ChaosAD]

You got efi fuel lines?
so is your ignition timing sweet then?

[l1ttle_d3vil]

yep, got 3/8 EFI hose from the tank to the pump, then from the pump to bundy tube which then runs to the engine bay, then EFI hose from the bundy line to fuel filter, then filter to the rail.
i had fuel leaking out of some of the injectors lastnight, then it stopped.

im not 100% sure about my ignition timing, but it is pretty accurate. i am told the dizzy can be within a mm or 2 of where it is meant to be and it should atleast fire up and just run rough. is this true or is it more likely .5mm for it to even run? i don't have an ignition timing mark on the bottom pulley that i can see. its been beaten with a hammer a few times and had a second pulley machined off it also (for a/c or p/s i think which i dont have).

[ChaosAD]

If you need a new pulley I could hook you up. Its for a FWD though so wont run the fan

[l1ttle_d3vil]

i'll be using an electric fan anyway so that doesn't matter. not sure if i'll need a new one though...thanks anyway

i spent about an hour turning it over tonight while changing just the spark timing, sometimes getting better results than others but it still didn't actually start.
is it a possibility the regulator on my fuel rail leading back to the return line is faulty? i'll probably look at setting up a pressure gauge on the fuel rail to check it, otherwise I can just replace it with another regulator to see if it makes any difference.
if i replace it is there any particular type of regulator i need? do i need one to suit the VL commodore pump, or the 4age engine/injectors? theres a redtop at pick a part, will the regulator off that be sweet? (presuming its not faulty!)

cheers

[ee904age]

Fuel pressure regs VERY RARELY crap out. If you release the pressure in the fuel rail (by undoing feed line, then doing it back up), then switch on your pump, and listen to the reg.

There should be a 3-5 sec pause then you will hear the fuel start flowing through it. If you hear fuel flowing straight away, its probably stuffed, but use a guage to double check.

P.S. email me some pics of your wiring, eg: coil, ecu, dizzy etc and Ill see if I can spot anything that may be causing this.