1jz vvti + autronic SM4 refuses to run properly

[blingcommander]

hey guys, i have fitted a 1jz vvti from a jzx100 into my silvia.

it has been stuck at the tuners for over 2 months as they can't get it to run properly. (it runs fine with the standard loom and ecu)
after trying many different solutions they have concluded that the crankangle sensor pickup is the culprit. being a strange number i assume (36-2 i think)

now i have heard of the early model 1jzs running this computer, but do they run the same CAS pickup?

what the tuners have now done is machine the number of teeth to an evenly spaced 12. supposedly it ran a heap better, but would break down heavily under load.

so now they have machined it down to 6 as of the start of this week.

so what i'm really wondering is does this sound right to you?
or do you know anyone that has an SM4 in their jzx100 even?
or can even point me in the right direction...

i really want my car running, and the tuners is a 3 hour drive away, so just popping in really isn't on the cards.

i'm located in eastern country victoria if that helps (car is in melbourne)

thanks

[George]

Why don't you just use the stock ECU? Have you upgraded the engine or do you plan doing so? I just wonder what's the purpose of nonstandard ECU for a stock (I suppose) VVTI engine.

Can you describe in details what's wrong with the engine now?

[blingcommander]

it runs a high flowed turbo at the moment, and will be getting bigger injectors as soon as i'm used to the power.

ok, so now it runs better, but they still aren't happy with it. now they are going to remove the injectors and check them out??
this is all they have told me

[JP]

What did Ian at Autronic say? I believe they had a firmware update that allowed it to run on stock triggers.

[blingcommander]

it is the latest version, i bought the computer new 4 months ago.

from what they have told me, you can input the amount of triggers, but they have said you can set no more than 16..

i'll be calling autronic on monday, but supposedly one of the tech guys (??) has been in a few times to try different things.

sorry if i seem a little vague, but i'm just going off what the workshop has told me.
i don't know a great deal about this sort of thing

[wilbo666]

One issue I had with my VVTi 2JZGTE was that the missing teeth are outside the firing period for the first cylinder...

I wonder if 1JZ VVTi is the same...



Cheers
Wilbo

[blingcommander]

yeah mate, exactly the same.

[grahamd]

On my VVTi with Autronic I left the 36-2 the same and just added another sensor for the Autronic picking up the front of the camshaft pulley. Fitted a marker on there.

[pato]

i recently fitted a autronic sm2 to a 2jzgte, but is apparently the same as a 1jz (non vvti, prob same as vvti tho)
i didnt pay massively close attention to the cas sensor when we put it in (was on a mates car), but iam pretty sure the cog only had 3 teeth on it.

i can try and find out more this afternoon.

i would of thought that your tuner should of known this straight away. If not, maybe its time to get a new better tuner ?

[JP]

the vvti uses different triggers to the non-vvti

[grahamd]

Yes correct, the VVTi's use a 36-2 on the crank and two 3th lobes on the cams.

[HIZOKU]

Lets hope this work as i want to see this s14 >_<

[blingcommander]

me too rob :S

On my VVTi with Autronic I left the 36-2 the same and just added another sensor for the Autronic picking up the front of the camshaft pulley. Fitted a marker on there.

how does that setup work? ie: 4 triggers per crank revolution? and not use the original CAS?

JP: how are they different? can you retrofit the older gear into the newer engine?

[JP]

I haven't compared the vvti and non vvti crank sprockets to see if they have a different number of teeth for the belt, but if they're the same you could swap them. You would still need to sort out a different cam signal for the reset. My preference would be to change to an ECU that doesn't require hacking up the factory triggers.

[blingcommander]

so they called me today and assure me they have the issue sorted.

the crank runs 3 teeth, the intake cam now runs 1.

supposedly it starts/idles and runs smooth as silk. they just need to fine tune it and it will be all good.

they will be writing out a detailed report of what they have done, and i will put it up here to save anyone else the headaches

[wilbo666]

I suspect that all you needed to do was to move the firing of the injectors and ignition over one to account for the missing teeth / reset being outside the first firing period...


I.e. Spark Goes 1&6,5&2,6&4

On a 6cyl engine there should be a firing event every 120deg...

With the VVTi triggering the ECU see the missing teeth while 1&6 are actually at 155deg BTDC.

If the ECU is using the missing teeth as the Cyl 1 reset trigger then this isn't going to work very as 115deg is out side the 120deg window that the ECU is expecting the No.1 TDC event in. The best you can get is 35Deg BTDC if you have the "No.1" output wired to Cyl 1


One way to get around this is to use the output that would normally go to 5&2 for cyls 1&6, and move the others down in the same fashion...

Cheers
Wilbo

[blingcommander]

thought i better update this. the crank is running 12 triggers, and the intake cam is running 1. both the sensors have been changed to aftermarket ones (sorry i'm not sure what brand)
went amazing but now it seems a ring has let go and the nice police officer decided the car would be better off the road.

if anyone is interested pretty much the whole setup is for sale as a whole, or in bits.
pretty much consists of an autronic SM4 with loom/sensors and pickups, injectors highflowed to 700cc, hypergear highflow turbo, synapse 40mm gate modded to fit the standard exhaust housing, AM performance dump pipe, NPC clutch to suit etc

pm me if you wish to know more

the good thing is that it will go towards a 1UZ conversion... and when that is engineered, a GT35 sized turbo