R32 GTR No start/backfire

[bnR32TH1]

Hello everyone. First post here with a question i haven't been able to find/fix. The car is a 1990 nissan skyline with an RB26. My problem is the car wont start however it is getting fuel and spark so i'm guessing its a timing problem but i cant get it nailed down. Ive used a timing light but have had problems with the COP and battery not being up to par. Also when i try to start it and apply full throttle for the fuel cut it ill get a couple backfires through the exhaust and an even louder one after i close the throttle again. I've tried adjusting my fuel both ways and adjusting the cranking advance to as far as 20*. The car will give a few kicks but not enough to get going. I have ls1 truck COP for spark and deatschwerk 1000cc injectors. using the required fuel calculator it gave me 2.9ms for fuel. Ive tried using the cranking taper curve to sweep the fuel from 80% at first to about 200% after 150 events. After searching for days and scratching my head i came here for help. Any help would be greatly appreciated.

Im using tunerstudio MS Ultra trial v3.0.05 and a pre assembled ms3 1.4.0 with the expansion card.

R32gtrNoStart.msq

2016-08-16_20.27.22.msl

[bnR32TH1]

Does anyone have an idea? At this point I'll try just about anything to get this car started

[jsmcortina]

A few thoughts:
Have you strobed the timing? on all plugs?
Are the coils wired up in the correct order?
Do coils and injectors work in test mode?

Try setting to "wasted COP" instead of "coil-on-plug" - while the phasing should be correct, firing through the exhaust is often associated with firing on the wrong phase?

James

[bnR32TH1]

I have tested the spark and injectors they both work in test mode. My coils are wired in firing order i.e. a=1 b=5 c=3 etc. When i tried strobing my timing light was no where close to the timing marks on my crank. Is there a way i can change phasing or is that have to do with my wiring?

[jsmcortina]

When i tried strobing my timing light was no where close to the timing marks on my crank.

Stop! Unless the timing is correct you shouldn't be trying to start it.

How close or far is "no where close" ? 10 deg? 20 deg? 60 deg?

Remove power to the injectors for now until you have figured out the timing issues.

James

[bnR32TH1]

Well im glad i stopped and asked.....

Factory timing is 20 btdc with marks from tdc every 5 degrees until 30 btdc. I don't see anything so i can hardly guess where my timing is at.

[suberimakuri]

I don't have any experience with RB's on MS, but I would go back through the manual and the settings in tuner studio.
Maybe the rising/falling edge is not correct? This can throw off timing by a lot.
With injectors and coils unplugged (or fuse out), what happens in the composite log, does it look good?
It should sync when cranking and show consistent rpm ~200rpm.
I've found unless I get cranking around 200rpm plus then I have issues on 4 cylinders. Not sure with 6 cyl, maybe it will handle lower cranking rpm.

[bnR32TH1]

ok so i had a bit of trouble with my computer jumping off a ledge without a parachute. Now that i have another one and got it hooked up to my MS i checked all my settings. In the MSExtra manual the ignition capture is falling edge, however in the diyautotune webpage on how to MS your rb26 the ignition capture is rising edge. I've tried both and only get sync with rising edge. I made a composite log for you all to see.

Composite.csv

i also have datalog of a short attempt to start.

RB26-turnover.msl

if anyone could help me understand more about the composite log whether it looks right or wrong i would really appreciate it. Thank you.

[prof315]

Ok you've definitely got a bunch of sync loss but as to the why I'm nor sure....

[bnR32TH1]

thats what i was afraid of, but where do you see it? when i open my daatalog in megalog viewer i have sync loss of 1 at the end when i stop cranking which doesn't seem right.

[prof315]

thats what i was afraid of, but where do you see it? when i open my daatalog in megalog viewer i have sync loss of 1 at the end when i stop cranking which doesn't seem right.

Look at the composite log, all of the red lines at the bottom indicate sync loss.

[bnR32TH1]

So ive been trying to figure out my sync problem but i cant seem to find the reason. When i look at the comp log or the datalog i dont see a sync loss or a reason for it. here are some picture i took of the log on my computer, am i missing something obvious?

MLVSync.PNG

MLVComp.PNG

I have the 1 degree input wired to the PT4 and the 120 degree input wired to the crank sensor. The ground for the sensor is also grounded to ms3 crank sensor ground in the shielded cable. Does the sync issue point to wiring or any other problem?

[bnR32TH1]

Does anyone see something wrong?

[suberimakuri]

You mention pt4 and crank.
I'm a little surprised but can't check docs.
Normally crank input takes the sensor with most teeth.
Then there is a cam input for tdc.
Then vvt type inputs end up on different inputs like pt4.
Sorry no RB experience.

[billr]

How about the spark timing, have you finally verified it is OK, on all cylinders/coils?

[bnR32TH1]

I have it wired up according to the directions on the manual, the rb26 settings in ignition input use pt4 for the high res signal. i know the spark timing is off because of the backfire but im not sure why and the crank angle sensor shows sync on my end. my only guess is the ignition input settings are wrong somehow and thats throwing off the timing. i dont even know what to try next.

[prof315]

You aren't using the correct viewer for the composite.csv log. Use the ignition log viewer for .csv logs. That will show you the sync loss in the composite log.

Something you might try.....

Noise Filtering: If it's turned on, turn it off. If it's completely off try turning it on. The one RB25 I have done wanted no noise filtering at all to work. Even the Global filter is set to 0.

[prof315]

You mention pt4 and crank.
I'm a little surprised but can't check docs.
Normally crank input takes the sensor with most teeth.
Then there is a cam input for tdc.
Then vvt type inputs end up on different inputs like pt4.
Sorry no RB experience.

The MS3 RB/OptiSpark/SR20 decoder requires that you use PT4 for the 360* hi-res signal and the crank input for the low-res signal

[bnR32TH1]

Looking at the composite log i couldn't figure out why my cam sensor input only activated when my crank sensor was on as well. I checked my wiring and realized when i added the pull up resistor to both the CAS inputs i messed up and daisy chained them i.e. my cam sensor was connected to my crank sensor which had the pull up to my 5vref. after i fixed that it started right up! once i cleaned everything up i got on the road to get a tune going and now she wont start again. i took a composite log of it this time and noticed a lot of sync error but i dont have the ignition viewer. can someone take a look at it and tell me what reason its saying its losing sync for? i would greatly appreciate it.

2016-08-25_11.59.59.csv

[bnR32TH1]

Does anyone see a problem or is it generic? I tested the pull up resistors and they are both still working. Does the sync loss reason explain anything else? Also i just want to thank everyone here thats helped. Its been frustrating but getting this car going felt like a huge accomplishment. Now i just need to do it again haha