36-1-1 and wasted spark or sequential

[Reverant]

Engine: Nissan QG15DE

It has a 36-1-1 crank wheel (17 teeth, 1 missing, 17 teeth, 1 missing) and 4 cam teeth.

I was thinking of running full sequential by cutting 3 of the 4 cam teeth, then running as dual wheel with missing tooth, setting the crank signal at cam speed (so the ECU would see it as 18-1 with one cam tooth).

That doesn't work however - I get the "Number of teeth/cylinder conflict", which I assume means I need an even number when I divide the teeth by the cylinders.

The crank wheel is inside the short block, so changing it requires removing the oil pan and crank - not going to happen.

Rover #1 mode requires a distributor (Wasted spark gives out a config error saying I need to set it to single coil) and this engine is sequential fuel/spark from the factory.

Does anyone else see a solution on this one? If not, I will just go on and write a custom decoder, but I would rather not if I can avoid it.

Thank you!

[jsmcortina]

Please post a composite log.

James

[Reverant]

I don't have a log yet, I'm assessing whether or not I want to accept this as a project from a potential customer, and if so I need to tell him whether this can work right out of the box or if we need to modify the cam, and to what extent. Hence all my questions and the research I've done so far on the bench.

James, if you can't think of anything, I'll grab a composite log and a crank/cam plot with a scope.

[jsmcortina]

A photo of the cam reluctor may help.

James

[dontz125]

A quick rummage through Google and eBay shows cam sprockets with a 1+2+4+3 pattern, not at all a simple 4-tooth arrangement.

[jsmcortina]

I'm pretty sure that's already supported.

James

[Reverant]

Maybe it's the QR25DE?

[Reverant]

Well, it's not the QR25DE, although very similar. The QR25 is 36-2-2, this one is 36-1-1, as the title says. Composite log attached.

[jsmcortina]

That's bizarre!

As you already know, it shouldn't take much effort to cut/paste/tweak the QR25DE mode to support this arrangement. What's the engine called?

James

[Reverant]

It's the QG15. I've already modified the QR25 code and it works (syncs and reads RPM without losing sync) but there's a bug somewhere in my modifications and the RPMs drop by about 18% every now and then for a split second, without losing sync though.

At this stage, I only connected the crank/cam sensors to the MS3, just to make sure that it can read them, so I haven't tested what the possible trigger offset may be on this engine.

[Reverant]

Engine is running great on the modified QR25 code. James, I've emailed you the code.

[resinrocket]

Hello All
Does anyone have a copy of this modified code? I am trying to run a QG18 engine in a K11 micra!
Sorry should have mentioned this is for a MS2 V3.
Many thanks.
Adrian.