4agze wiring and ECU

[keiichi]

Car - KE70

motor - 4AGZE

use - project, just bought it, not running

problem - wiring is a mess, did not come with ecu

occurs/started when - i bought it?

personal situation - my knowledge of wiring and ECU's is limited.

(will put pics up tomorrow if it helps)

ok so for some reason i bought a ke70 with a 4agze in it, not running, it has no ecu in it.

apparently it used to have an aftermarket ecu - brand name was something like ingen which had a hand controller.

the plugs are all intact and available, it used to run (drive) on the aftermarket ecu until it started to fall out of tune or something like that and got parked and left.

further information - runs off a normal distributer (as opposed to coil-packs) with (i think, at a guess) the CAS coming out of it. it appears to be basically stock except for an r33 intercooler, pod filter and extractors. pretty sure it is map sensored, not airflometered.

my question is - do i need to get an aftermarket ecu and have it re-tuned? or can i use a standard 4agze ecu?
orrrr..... wtf should i do next? what would be the best way to go about getting this running.

Thanks in advance ^_^

engine
http://www.ae86drivingclub.com.au/dcimages/2/0/8/58707.jpg (http://img697.imageshack.us/i/pc050365.jpg/)

where the coil/ignitor used to be.
http://www.ae86drivingclub.com.au/dcimages/2/0/8/58708.jpg (http://img823.imageshack.us/i/pc050366.jpg/)

only two ecu plugs
http://img256.imageshack.us/img256/6700/pc050368.jpg (http://img256.imageshack.us/i/pc050368.jpg/)

two plugs not connected. TPS on the left and on the right, is that a cold start injector?
http://img547.imageshack.us/img547/1155/pc050367.jpg (http://img547.imageshack.us/i/pc050367.jpg/)

[keiichi]

also how can i tell what version of 4agze i have?

[Sam-Q]

there would parts of it you could use with an OEM ECU but for the greater part you would need a very significant rewire


However fitting a different standalone ECU to the loom you have now is unlikely to need major work, you might need to make some basic changes after you swap the plugs but it shouldn't be too bad.

[keiichi]

ok so if the signals that are sent back to the ecu to form the map are factory then shouldn't a factory ECU be sufficient?

hmmmm and, why do you think i would need a rewire? do aftermarket ECU's come with their own loom?

it is possible that the ecu that used to be in there was just a piggy back on the OEM, the guy i bought it off didnt seem very sure about alot of it... he told me the previous owner had an aftermaket ecu - didnt specify what kind or type - with a hole cut in the glovebox for access to the ecu or something with a plug in it so you could plug in a controller and adjust shit. judging by the 4agze technology the only thing i could see being adjustable with the setup on this engine is maybe just the A/F ratio.
ignition timing is run off the distributer.
SC clutch engages when the computer tells it to, i dont see why the when would need to be changed.
A/F ratio shouldnt need to be changed just because of a pod filter.
So yeh, i just cant see why a standalone would be required in the first place. or even a piggy back, since the only thing adjustable would be A/F ratio which would be right from factory anyway.

Am I missing something here?

[Sam-Q]

well I am not exactly experienced as I have only been playing with 20V silvertop ECU's (aweful things!), and from that experience I have found that they have much more complex wiring paths and even though what your proposing sounds completely logic in practice it's likely to be very different.

[keiichi]

would it be wise to get a standard ecu with say for eg an hks f-con that comes with the replacement mass air sensor and take it somewhere to get tuned? :S

*edit* nvm that. just found out these are meant for turbo conversions.

[86TRD]

what colour is your dip stick? this can be a sign to what model motor it is, my 4agze is from a ae101 which has a grey dip stick, i think maybe ae92 or aw11 have a yellow dip stick.

[keiichi]

what colour is your dip stick? this can be a sign to what model motor it is, my 4agze is from a ae101 which has a grey dip stick, i think maybe ae92 or aw11 have a yellow dip stick.

interesting - my dipstick is grey yeh.

[keiichi]

k - did a bit of research and inspected the car some more. it has a custom loom, will put some pics in the op in a min.
for eg. 4agze loom to ecu has connectors 16pin, 22pin and 26 pin. the ecu connectors on this loom are 16pin and 20pin. there are no wires or connectors to MAP and TP sensors. or i have looked at it wrong, TP and cold start isnt connected. there actually appears to be no MAP or AFM.

anyone know where the MAP sensor is supposed to go?

what is the next step?

best bet would be to just get a standard ecu and loom?

[Skylar]

You have an AW11 engine I think. Someone will know the answer for sure.

Best bet is to get correct loom and ECU or start over with an aftermarket ECU but looks like you're missing some plugs so you'll need a loom anyway. If you get a factory loom and ECU, you will have to get the AFM, coil/ignitor, etc. I'm pretty sure you can safely run either AW11 or early AE92 loom and computer but you'll need to switch to coilpacks for AE92 stuff.

[keiichi]

awesome thankyou!

so, would i be correct in saying that the dizzy models have AFM not MAP?

[Skylar]

Dizzy for sure is AFM but AFM did come with coil packs in early AE92, then they switched to MAP for smallports. AFM/bigport engines were 8.0:1 comp so you can use either AW11/AE92 AFM computer and have the engine run good.

[keiichi]

ah damn, was hoping i might have the more powerful version. should still be a bit of fun :)

[Nikkojoe]

AE92 AFM engine. Your dizzy is off an ae86 4age, not an aw11 (aw11 are quite different).

The ae92 and onward had a second hole cut out (the small one) on the cam gear covers for a bracket they ran. AW11 did not have this bracket.

Also ae92 onward have the top water outlet angled forward more, aw11 point up like an ae82.

Lastly, the supercharger outlet pipe has been modified, however it used to go straight up where as aw11 went backwards to the rear of the engine.


Now what i suggest you do is you can get an ae92/aw11 setup if you wish, but i find they can be a little hard to get. I ran an ae101 loom, ecu, map, knock sensor on my ae92 afm engine. It ran ok, but a lot of things were hacked to the loom so it never ran it's best. It might be easier to find an ae92 map loom and ecu with map sensor, igniter, coils, and knock sensor. Swap your dizzy to an ae92/3 smallport dizzy (same inside as a cas, and usually a lot cheaper - downside is you still have a dizzy cap on it) and it should work. You will need to change one plug on the ae92 map loom, and that is the tps plug (ae92 map are round plug vs afm square). The rest is the same pretty much.

Good luck

[Skylar]

Damn your excessive knowledge of 4A's!!!!

[keiichi]

fantastic thankyou nikko!

here is a better pic of the dizzy

http://img132.imageshack.us/img132/3071/pc060365.jpg (http://img132.imageshack.us/i/pc060365.jpg/)

any idea what that plug is with the grey wire leading to the grey box? i thought maybe CAS to begin with but it only has 4 signals.

can i use that dizzy if i stick with aw11/ae92 dizzy/afm loom?

made this up today - should help a bit :)

http://img26.imageshack.us/img26/4782/pc060373.jpg (http://img26.imageshack.us/i/pc060373.jpg/)

[Skylar]

Can't use that distributor (24/4) with GZE. GZE use a 24/1/1, ie smallport distributor/CAS. Anyway, you need a 4 wire CAS/distributor, not the three wire you have now.

Grey box must be a signal converter to allow the ECU to read from the CAS? Maybe it's one of them things America 4A-GE corollas had to process the CAS signal before it reached the ECU.

[Nikkojoe]

Problem with your dizzy is it has nothing stock in it :P

So you would need to find a dizzy to suit the aw11 gze first (ae92 onward used a cas and coils, not matter if it was afm). But really, just find an ae92 map loom like i said with the info above, far easier.

[keiichi]

So you would need to find a dizzy to suit the aw11 gze first (ae92 onward used a cas and coils, not matter if it was afm). But really, just find an ae92 map loom like i said with the info above, far easier.

easier to find one or easier to put together? using the ae92 map loom i can still run the stock ae92 map ecu? is it possible to use the dizzy that is there now to generate the CAS?

[keiichi]

Can't use that distributor (24/4) with GZE. GZE use a 24/1/1, ie smallport distributor/CAS. Anyway, you need a 4 wire CAS/distributor, not the three wire you have now.

Grey box must be a signal converter to allow the ECU to read from the CAS? Maybe it's one of them things America 4A-GE corollas had to process the CAS signal before it reached the ECU.

hmmm interesting - the previous owner told me it ran off an american brand ecu.

[Skylar]

When I say CAS, I mean the crank pickups in the distributor. and no, you need a smallport 24/1/1 distributor. No way to run the bigport distributor with any GZE computer.

[Nikkojoe]

easier to find one or easier to put together? using the ae92 map loom i can still run the stock ae92 map ecu? is it possible to use the dizzy that is there now to generate the CAS?

Easier to find and utilise! Using an ae92 map loom with correct ecu (ae92 map) you will need a 4agze cas OR ae92/3 adm or jdm smallport dizzy at minimum. I may have a smallport dizzy if you end up needing it. You can't use the dizzy you have now because:

1. it aint stock, all the original shit has been gutted in it and an custom pick-up has been used.
2. even if it was still all the factory shit inside, its a 24/4 dizzy by nature which does not work with a gze, only a bigport 4age (which skylar has pointed out a few times :P)

Gze setups are picky, cant slap shit together and hope they work ok. Really need to retain a lot of the factory stuff for them to work at their best, which is sometimes why when people go aftermarket ecu on them there are no gains (sometimes steps backwards!).

[keiichi]

hmmm yeh, i keep hearing i should go aftermarket ecu.

and yeh, point finally taken about the dizzy :P

i will probably want your dizzy yeh if you want to sell it to me, as i will probably follow your advice. i need to do some more research though, there does seem to be some logic in going aftermarket but meh too tired to think about that now lol.

[keiichi]

been doing a bit more research, and i think that going aftermarket ecu would be the way to go, any recommendations for a simple, user friendly affordable one?

i got some power to the car today and all the electrics work, it seems like a mess but it is all operational, and i think i figured out what is up with the dizzy and the grey box... so, i'm going to go through a few things and if anyone can correct me or confirm, please do! :) pictures below for reference.

there is a switch in the dizzy as you can see, it picks up one signal in four quarters of a rotation. each one of those cam nodes passes the switch (sends signal) at the same time the rotor passes the spark sender. follow the grey wire back into the grey box. i traced the wires out of the box. starting from the bottom they lead to:
1. ECU
2. ECU
3. Sliced into wire between starter motor and KE70 OEM fuse box.
4. Power relay.
5. Coil/Ignitor.
6. Earth.

Now I was thinking that, for each time the rotor passes one of the spark senders, normally, the spark is preloaded and is sent as soon as it passes. The rotor 'blade' is pretty wide so is it possible that this setup that is on there is taking the signal and sending it to the ECU so that you can tune when the spark is fired as the rotor passes. there isnt much there but there is enough to allow some adjustment of when it can fire.
So in conclusion, this setup is intended to allow tuneable ignition timing while maintaining a dizzy type ignition.
Am I right?


http://img525.imageshack.us/img525/5920/pc070364.jpg (http://img525.imageshack.us/i/pc070364.jpg/)

http://img132.imageshack.us/img132/3071/pc060365.jpg (http://img132.imageshack.us/i/pc060365.jpg/)

also another question... from the intake plenum there is a vacuum hose that leads to a T intersection, one way going into some vacuum cylender thing on the SC i think, the other way heading into the cabin and ending next to where the ecu used to be. is it possible that hose was or can be connected to a MAP or MAF sensor or some sort? which in my understanding would be a required reading for an aftermarket ecu.

and thanks again for the input in this thread so far, it's made my life alot easier :D

Any recommendations for an aftermarket ecu?

[Skylar]

Ugh get rid of that crazy box and pick up a standard loom and (smallport) distributor. Wire in an adaptronic or just buy a patch harness from kaizen garage. Tune. Enjoy car.
Not saying you can't use that loom but it's a bit of work.

You'll get much better drivability if you run stock 24/1/1 trigger than that 4 tooth wheel.

Hose to cabin would have connected to the on-board MAP sensor in the (aftermarket) ECU.

Your electronics terminology is funny. :hehe:

[keiichi]

My terminology is such because I am making it up as I go.... I'm a self taught person, I had very VERY limited knowledge of ECU's and all that shit before I bought this car... I'm just like meh whatever I'll figure it out. Now my head hurts lol but its fine. I feel like I have crammed in alot in the last 24 hours.

I have no idea what this 24/1/1 business is.

I'm also thinking of getting a Megasquirt or Microsquirt. There is tons of DIY guides on the net, software etc.
I should be able to get one of them, trace back each wire from the original ecu's plugs that are there now, cut and rewire in to the squirts correct sockets (from what i understand each pin for its plug it comes with is a different receiver), get a MAP/MAF for that hose, wire it in. Plug into laptop, AND THEN WING IT!!!!! hahaha

Still don't understand why the crazy grey box is so crazy... maybe it just my kind of crazy cause I find it very intelligent.

Also, did a comp test today... 135 across the board sound normal?

[Slimer86]

Save yourself many headaches, and get a new loom and ecu.
Source a dist from an AE92 smallport to use as the crank angle sensor, and get a new loom.
If you use that loom, you don't know the history of it, it already looks like a headache, why give yourself more pain in the long run when it doesn't run as you would like it?

Wiring is painful when its not right, and trouble shooting can be very costly.
I was taught during a seminar for an Australian aftermarket ecu, you can have the best ECU, but if the wiring isn't up to the task its next to useless.
P.S, that alternator 12+ and charge light wiring is making me nauseous, I hate to see what the rest of the engine loom is like.

[Skylar]

Hey, not giving you shit for your terminology, I just find it amusing, and sometimes I don't know what you're talking about.

24/4 is that trigger pattern you currently have in that distributor. 24 tooth (at the back) and 4 tooth (front) wheels providing 2 signals to the ECU. 24/1/1 is the newer style so they can run sequential/waste spark. It has the same 24 tooth wheel but the wheel at the front only has one 'notch' in it but two separate sensors read that wheel. Sends 3 signals to the ECU.

MS shouldn't be hard to do. You'll learn a lot reading the megamanual. I need to go buy one.

crazy grey box is crazy because it doesn't need to be there. You have more wire terminations, and a critical ignition component sitting in the engine bay which isn't required. Most ECU's can process the signal straight from the CAS without a crazy grey box.

[keiichi]

i didn't think you were giving me shit for my terminology, i'm just frustrated cause i wish i just new this stuff already lol.

i think, from what i have seen, there is no CAS on this engine atm. unless that pickup to the crazy grey box can be considered one, but doesnt there need to be a pick up from the 24teeth and that would be the CAS?

so im thinking, still get the MS, an ae92 dizzy to use for the CAS and a MAP+Coilpack loom and rewire. its either that and wire up the MS and see what happens. OR, i can try find out off the previous owner what the ecu brand name was and buy another :S

[Skylar]

CAS refers to anything that picks up crank rotation and converts it to a electronic signal for the ECU to read. Normally consists of one or two patterned wheels or discs and the sensor(s) to go with it. So you could call that ultra-primitive set-up on your engine to be a CAS and use it alone to trigger whatever (aftermarket) ECU you choose to run next but only batch injection and distributor. Hell, people have used points to trigger an ECU when no other easy option was available. But as I said, a 24/1/1 dizzy would provide much better drivability through banked or sequential injection.

If you decide to use that harness and an MS, you have to decide what ignition set up you're going to use. The harness is only configured for banked injection and waste spark (this may have been deleted when reverting to big port distributor). MS2 only has outputs for distributor and two for injectors. If you want sequential you can run MS2X and extra boards for 3/4 injectors and another for 2/3/4 coilpacks and you need the board for the second reluctor input. Microsquirt has 2 injection outputs and two ignition outputs, shit's expensive as it's prebuilt and fully sealed. Buy an MS3, will run a V8 in sequential and do way more than you need it to. You can run the jb-perf boards for extra injectors/ignition outputs(cheaper) or buy the plug in MS3X board which has all 8 ignition and 8 injector outputs and other stuff.

Confusing, eh?

[keiichi]

I was doing ok until "If you want sequential you can run MS2X and extra boards for 3/4 injectors and another for 2/3/4 coilpacks and you need the board for the second reluctor input."

[Skylar]

You need to read the previos sentence too if you want that to make sense, so it reads:

"MS2 only has outputs for distributor and two for injectors. If you want sequential you can run MS2X and extra boards for 3/4 injectors and another for 2/3/4 coilpacks and you need the board for the second reluctor input."

MS2X is an optioned out MS2 which allows you to take logic signals from unused pins on the CPU. These signals are very low current and only 5v. You need the boards to boost the signal to 12v plus throw some real current at an injector. You solder into some points and run these to separate boards that mount inside the ECU to run your 3rd and 4th injector. Same deal for the waste spark/sequential spark. Take unused pins and condition the signal so it can trigger a coil to spark. Not really needed if you go and raid 3 Camiras for Bosch 008 ignitors. The spark output on a MS can directly drive a coil without an ignitor, up to you if you want to run external ignitors or solder up a board that does the job of the ignitor.

The last bit about the reluctor: Toyotas run a variable reluctor pick-up/sensor in the distributor to sense the rotation of the wheel. This signal requires conditioning through a LM1815 chip and a bunch of resistors and capacitors needed to make the chip function in the correct mode. The MS v2.2, v3, and v3.57 PCB's only have one signal conditioner. The newly released MS3 daughterboard has one built onto it while the MS2 daughterboard doesn't.

[keiichi]

wow, why would MS only be able to read two injectors, you think they would set it up to atleast read four :S

that actually makes sense now. so, if one were to spend a bit extra on a more commonly used thing like haltech or something, it would come with built in gear for atleast 1-4injectors, 1-4coilpacks etc yeh? getting an MS does sound like a bit of fun though and a good learning tool.

[keiichi]

also i called the previous owner to find out what the old ecu was.... injen he said, looked them up, they dont make ecu's (b-_-)b


btw... anyone know how to tell if you have low or high impedance injectors?

[Skylar]

The two fuel outputs and single ignition output are plenty to run a 4A. The. 4A ecu only has one fuel output and each injector squirts a quarter of the required fuel 4 times a cycle.

Adaptronic can do seq. spark and fuel, microtech lt8x or whatever it is these days is also four cyl seq. Haltech probably has a 4 cyl seq model but I dunno what it is off the top of my head. Or you could get an ms3 which is capable of running 8 cyl seq.

Impedance is resistance, you know how to use a multimeter right?

[keiichi]

ah yep so check the ohms resistence if it is about 2.5-3.0 its low if its 12ish its high? do i need to turn the car over or just whack the meter on?

[Skylar]

Just measure the across the two pins on the injector.

Yeah, they say below 4 is low and above 11 is high. Something like that, I know I'm not spot on about the numbers but it's thereabouts.

[keiichi]

cool, just checked it, they are 3.7. then i tested the connector and it was 3.7 aswell - would i be correct in assuming that the correct resistor is installed somewhere along the line?

i better go do some work but ill be back with more annoying questions for you or whoever wants to get involved :D

[Skylar]

"then i tested the connector and it was 3.7 aswell - would i be correct in assuming that the correct resistor is installed somewhere along the line?"

Ya lost me here. You measured the connector while on the injector or the plug alone? It sounds to me like you were measuring the output impedance of the ecu.

What resistor are you talking about?

[keiichi]

i measured the injector alone then the plug alone.

i read somewhere that if you have low impedance injectors you need a resistor or you'll burn the ecu. i assumed that if the plug had the same impedance as the injector the circuit is resisted so the ecu didn't get burnt.

[Slimer86]

4agze's run a solenoid resistor pack prior to the injectors. (wire colours, red with a white stripe, and red with a black stripe)
If you measure around 3.7ohm across the terminals on the injector itself, they are low impedence.
A small port na 4age has injectors of 14.4 ohm's.

[Slimer86]

Looking at your wiring diagram, you can see the solenoid resistor inline with the 12+ power from a relay. (edge of the far left page)
Black wire with orange stripe should be the power supply line, probably from IG2. (power feed switched direct from the ignition barrel).
The other two wires are for injectors 1&2 (RW) and 3 &4(RB).

Check out the diagram on club4ag.
http://www.club4ag.com/technical_main.htm
ECU Connection Pin Out

4A-GZE AE92 Japan

AE92 Supercharger Levin / Trueno GT-Z 1990-91

Japanese Specification 8.9 Compression, Distributorless Ignition, MAP

Having another look at your drawing, is that the USA AW11 4AGZE drawing from Club4ag?
If so, the 12v+ input to the solenoid resistor is a black wire with white trace, and output:
1&2(Blue), 3&4(Red)

[keiichi]

yep i got the aw11 diagram. and found it yeh. having looked at the diagram and at my engine, the wiring seems to all be done properly, albeit messy.

[Skylar]

I see.

Some ECU's can handle low impedance injectors and some can't, requiring you to run a resistor pack. Depends on what ECU you run.

[keiichi]

anyone have experience with microtech ecu's? ive been reading up on them, they seem pretty common and easy to get a hold of (also in my current price range).

[Slimer86]

Use the ecu which is familiar to the person you will have tuning the car.
See if the tuner is familiar with Microtech and for any model recommendations etc.