1JZ faking IGf with a circuit

[Wizzard]

Hi guys,

I just put a 2J in my car and need to fake the IGf signal for the ECU. I am using stock ECU with an emanage ultimate. I have used LS2 coils with built in ignitors, and its all set up and rocking. I am having problems with the IGf (error 14). I do electronics and have tried to make up a small circuit of transistors to fake the IGf, but its not working.

Currently I have 3 transistors with resistors like the IGt/IGf single circuit found on here, hooked up to IG1, IG5 and IG3 (output on ECU, waste spark from the 1JZ ECU I believe). I still get the same error.

Maybe I am using too high resistors so not enough current going to IGf, does anyone know what current it expects? Or does anyone have a working circuit design? Seems to be nothing on the internet.

Justin.

[Mos]

Currently I have 3 transistors with resistors like the IGt/IGf single circuit found on here, hooked up to IG1, IG5 and IG3 (output on ECU, waste spark from the 1JZ ECU I believe). I still get the same error.

There's no link?
Non-VVTi JZs are not wasted spark - they have 6 outputs and would need 6 igf pulses - try that first.
If you're wasted sparking, are you sure you got the phasing correct?
What JZ ECU are you running? Your setup sounds like a mess.

Maybe I am using too high resistors so not enough current going to IGf, does anyone know what current it expects? Or does anyone have a working circuit design? Seems to be nothing on the internet.

The IGF that I have looked at are square waves, I'd expect the 2JZ to need a squarewave too. There is a time delay between the beginning of the trigger pulse and the igf pulse; if you set igf at the same time as igt it might not register as a valid igf signal. You shouldn't be concerned about the current - it's only voltage level based, not current. Have you looked at the waveform that your circuit provides?

Take a look at this, page 4:
http://lextreme.com/Adaptronic/1UZFE...ationNotes.PDF
I havent tried it but in theory it works for 1UZ.

Mos.

[wilbo666]

As Mos says,

2JZ-GTE non vvti is NOT wasted spark.

You should have your emanage setup to run the spark in exactly this fashion. i.e. direct spark.

I'm not familiar with the LS2 coils, is it single coil / igniter per unit and you have 6 of them? [edit, yes the LS2 coils are single coil and igniter]

The stock 2JZ ecu expects an IGF signal for each spark event.

The e-Manage Ultimate and the stock ECU could/can control the 6 spark signals.

I did have a cro plot of the IGF ect signals from a JZ igniter, but can't seem to find it any more...

You prbly read this thread and thought u needed 3?
http://soarercentral.com/sc-forum/me...tml?1209208850

Also Autoshp101 doc that might help...
http://www.autoshop101.com/forms/h23.pdf

Mos as a note the autoshop doc seems to show a different waveform to the Adaptronic waveform?

There is also this...
http://kerth.dyndns.org/supra/files/...Gf_circuit.pdf

I suspect on the 2JZ you will need to diode the 6 ignition outputs to the IGf generating board so you get an IGf signal for each event

Going off the 7mgte circuit that the PDF relates to, it would seem that grounding the IGf line when the ignition output line is high works...

Maybe give the below circuit a go?


Cheers
Wilbo

[Mos]

Mos as a note the autoshop doc seems to show a different waveform to the Adaptronic waveform?

Yeah, and it's different to what I scoped (1G-FE) as well .. generational variation I say

Maybe give the below circuit a go?
<snip>

That won't do time delays, and won't do fixed pulse width, but I guess it depends how critical that is - the circuit is simple enough to try anyway.
On the 1G-FE the igf was always the same time away from the trigger edge, and the same pulse width, regardless of rpm and regardless of the igt pulse width.

I need to make one for the 1G at some point... now that Ed's nugget is finished I might actually have some time to try...

Mos.

[Wizzard]

Guys its a 2J in a Soarer (not a mess, as you would believe, all quite awesome). So I am using my 1J ecu, as rewiring my Soarer for a 2J ECU would be ..... The 1J ECU runs 2J's very very well, I can assure you (as you all know).

Ok I thought the 1J was a waste spark, I have been given bum info, no problems will whip up that circuit Wilbo looks good to me electronics brain. Also I could just add another 3 trans. to my current circuit.

[wilbo666]

Yeah, and it's different to what I scoped (1G-FE) as well .. generational variation I say


That won't do time delays, and won't do fixed pulse width, but I guess it depends how critical that is - the circuit is simple enough to try anyway.
On the 1G-FE the igf was always the same time away from the trigger edge, and the same pulse width, regardless of rpm and regardless of the igt pulse width.

I need to make one for the 1G at some point... now that Ed's nugget is finished I might actually have some time to try...

Mos.

K,

I don't recall what the CRO showed when I checked mine...


You are 110% right that the circuit I showed is very simple, but I was just going off the fact that people have said it has worked in the past!


Wizzard: Alarm bells should have been ringing in regards to wasted spark when you looked at the ECU pinout and saw IGt1 to IGT6

Cheers
Wilbo

[Wizzard]

Ah yes...hmm. Wilbo that soarercentral link is actually me ( I am Justin). No information for waste spark was in my brain from long ago. Also recently, read somewhere that some guy did one of these circuits with 3 transistors (hence why it sort of made my brain go...hmmm waste is right).

Now I know! Never fiddled with ignition too much...first time, I will get it to work. If your circuit wilbo doesn't work, I will modify that one Mos send me from lextreme, with the diode inputs (from each) one, to give that RC circuit output onto the IGf.

[Wizzard]

Ah Wilbo, I know, but someone stated a long time ago, that even though there was 6 outputs it was wasted spark.

I betcha the rumour started (we are talking 4 years ago now) because the injectors are batched fired....

I haven't needed to research anymore since then...
+1rep, although you guys don't need it.

[Mos]

Guys its a 2J in a Soarer (not a mess, as you would believe, all quite awesome).

Was talking mess engine management wise...

So I am using my 1J ecu, as rewiring my Soarer for a 2J ECU would be .....

Rubbish .. rewiring any car properly is not a mess .. Running a car on the wrong ecu is just as much of a mess as a dodgy rewire....
And I rest my case

The 1J ECU runs 2J's very very well, I can assure you (as you all know).

As you have stated in your opening post that it doesn't run?
I'm not trying to annoy you, but seriously, please don't try to convince anyone that running a 2JZ on a 1JZ computer is a "better" solution.... it's like running 20psi on a 2JZ with a FCD and a RRFPR... sure it works, but that's all that can be said...

no problems will whip up that circuit Wilbo looks good to me electronics brain. Also I could just add another 3 trans. to my current circuit.

Easy enough to try all combinations.

Ah Wilbo, I know, but someone stated a long time ago, that even though there was 6 outputs it was wasted spark.

It's amazing how misinformation spreads.

I betcha the rumour started (we are talking 4 years ago now) because the injectors are batched fired....

Who started the rumous that the injectors are batch fired???? (THEY ARE NOT!!!)

It's like those morons who think the Altezza 3S-GE is alloy block....

Mos.

[wilbo666]

Who started the rumous that the injectors are batch fired???? (THEY ARE NOT!!!)


Mos.

1JZ-GTE is batch fired injectors...

2JZ-GTE is sequential injection...

I think he was referring to 1JZ

Cheers
Wilbo

[Wizzard]

Thanks Wilbo, thought I was going crazy for a second there. I make resistor packs for the Soarer and damn sure, Inj 1-4, 2-6, 3-5 are fired in pairs.

My first 2J, so didn't know that they fired individually on their computer, good info to know.

Plopping a 2J in a Soarer is very easy, but you put the 1J loom on the engine and I only had to modify one plug.

Its not running because of this IGf crap. It was my choice to go aftermarket LS2 coils as it worked out $400 cheaper. Just required this extra research for this circuit. Should have kept the originals I know...you live and learn!

[Mos]

I thought I was going crazy

[oldcorollas]

resistors on injector power in pairs can still be fired individually tho...? they are coupled in the ECU, or ECU only has 3 inputs from injectors on 1J?

[wilbo666]

resistors on injector power in pairs can still be fired individually tho...? they are coupled in the ECU, or ECU only has 3 inputs from injectors on 1J?

1JZ-GTE ECU only has 3 pins to drive injectors...

If it can somehow still fire them sequentially with that I need a new brain?

And stock 1jz-gte doesn't has high impedance injectors, so no resistors for them. For reference tho JZZ30 has two separate power feed wires in the loom for injectors tho

Cheers
Wilbo

[Mos]

VVTi 1JZs have sequential injection - 6 outputs - but not relevant here.
The separate power feeds are only to reduce the current through the pins, they connect to the same conductor in a junction block.