4g63 Trigger sync tooth

[bluegsx_1995]

Hello, I've installed the furyx into my 2g dsm and I'm having issues with cylinders 1&2 not firing, it runs very poorly on cylinders 3&4 only. 

Setup: Denso COP wired for direct spark, sequential fuel injection, kiggly 12 tooth crank sensor, 1g dsm CAS with one of the optical slots blocked (see trigger scope attached). 

Checks: I've verified wiring to correct cylinders for ignition coils and injectors using a timing light and LED strip light, mechanical timing, weak coil(s) or cracked spark plug(s), verified compression.. and finally, trigger settings (see current settings attached). 

Maybe I've missed a thread on this but I am wondering how to determine the sync tooth under trigger 1 parameters? With the 12 tooth trigger do I consider the tooth after TDC as #1 and count from there comparing to the cam sensor until the cam sensor is about to trigger and its the following tooth? Can the count be determined from the trigger scope? 

Also to double check, firing order should be set to 1342, correct?

Thanks in advance!

TriggerScopeLog4_18_21.llgx PC Datalog - 2021-04-18 1;09;03 pm.llgx

[Adamw]

Your scope is fine and in the log it looks like the ecu is happy with the trigger.  Sync tooth isnt relevant in this case since no VVT.  

Have you verified base timing?  Your trigger offset of zero would be would be a big coincidence if that was correct.  

When you say it is not running on cyl 1 & 2 do you have a spark on those cylinders if you put a light on them?

[bluegsx_1995]

Thanks for the fast reply Adam!

Yes, I have spark on cylinders 1 & 2 along with injector pulse when it's running, verifiedwith timing light and LED strip. But I can pull the primary side of the coils off or injector connectors off and no change in running condition. 

I was curious about the timing offset. I was able to set base timing with an offset of -2° but this doesn't match other threads I've seen where they are having an offset of roughly 270°. The harmonic balancer has marks 180° apart, it could be 180° off I suppose. That's also why I was checking on the firing order. Seems it could be simply firing at the wrong time. 

Thanks again!

[Adamw]

With mulittooth mode, the trigger offset is measured from the tooth on the crank that imediatly follows the cam edge back to TDC #1.  So with an offset of zero that would suggest the edge of the cam window that you are using is somewhere very close to TDC.

Looking at the stock evo 1-3 cas (it may be the same as 1g but might not be too), they have one of the "cam" falling edges at about 50ATDC and the other at about 340ATDC.  So if the 1G cas is similar I would expect to trigger offset to be somewhere around one of these values, say +/-30deg.  

Its hard to imagine a reason why it would run on any cylinders at all if the ofset was wrong as it would be wrong by the same amount on all cylinders. 

As a reality check I would probably turn the engine over by hand to TDC#1 then pull the lid of the cas and see where the window is in ralation to the sensor.  If one edge is right under the sensor then your offset of 0 is correct.  

 

16 hours ago, bluegsx_1995 said:

Also to double check, firing order should be set to 1342, correct?

Correct.

 

Can you also confirm, when you do the ignition test, does cyl 1 spark when you test ign 1, cyl 2 when testing ign 2 etc...?

[bluegsx_1995]

27 minutes ago, Adamw said:

Can you also confirm, when you do the ignition test, does cyl 1 spark when you test ign 1, cyl 2 when testing ign 2 etc...?

I have confirmed this, cyl 1 coil sparks when testing coil 1, ect - and likewise for the injectors. 

Attached is a picture of the CAS when at TDC. I'm probably misunderstanding but I turned the engine over by hand and got the open slot close to the optical sensor, then rotated the engine back to TDC which resulted in rotating 360deg+ approx. 50deg.

[bluegsx_1995]

After some trial and error with the offset I got it to obviously run on all 4 with a 360deg offset. I was able to get it to a relatively steady "idle" rpm and set base timing with a 357deg offset. Is that okay or will it result in longer crank times? 

I wonder if I should change the position of the CAS 180 deg to achieve a more reasonable offset. 

[Adamw]

No, offset makes no difference to start up delay.  The engine can start as soon as the ecu has seen the cam tooth.  

[bluegsx_1995]

Thank you!