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LOG 1 on 10/23 ECU Pulling 5 degrees

Posted: Thu Oct 24, 2019 10:14 am
by my1path
Matt wrote: Wed Oct 23, 2019 8:01 pm Might be okay, customer returning one this week for checking
Let me know if that doesn't work out or if you need more time with one. If I send you one it would be yours to keep for R&D.
Matt wrote: Tue Oct 22, 2019 1:01 pm Post tune and log file so I can check it here. I don't have any M30 ECUs to check on however
Log from this mornings short drive to work.
Tune used with this log.
ADR file was modified to include two temp enrich tables

Ambient temp was about 50F/10C

LOG 2 on 10/23 ECU Pulling 5 degrees

Posted: Thu Oct 24, 2019 10:29 am
by my1path
Matt wrote: Tue Oct 22, 2019 1:01 pm Post tune and log file so I can check it here. I don't have any M30 ECUs to check on however
Another log from this afternoon. Ambient temp was about 86F/30C
Same modified adr as above.

Tune was modified so 25 degrees covers most of the map. Trying to make the problem easier to spot by ruling out cell averaging and providing a common number to more easily spot deviation.

It looks like anything over 2700-3000 gets 5 deg timing pulled "warmup timing RPM max" happens to be 2600 so I tried setting it higher but nothing changed. I also tried the same with "warmup timing TP max" with no luck.

Re: ECU Pulling 5 degrees? no clue why?

Posted: Fri Oct 25, 2019 9:28 am
by Matt
Thanks. Yeah this one is on its way... we modify M30 ECUs for Nissan Patrol Y61 TB45 but this one apparently has no spark/injector?! So need to check it on the bench

Re: ECU Pulling 5 degrees? no clue why?

Posted: Sat Oct 26, 2019 2:07 pm
by my1path
Matt wrote: Fri Oct 25, 2019 9:28 am we modify M30 ECUs for Nissan Patrol Y61 TB45
That's Pretty cool!

Re: ECU Pulling 5 degrees? no clue why?

Posted: Mon Nov 04, 2019 11:05 am
by Matt
Yeah I see it. We have TIMING_MAP_OFFSET=0 for now, but that is almost like it should be 5 when RPM >= 2500-2600. Load doesn't seem to matter so much. This particular ECU is so strange with what it does with the timing, none of the other ECUs work like this...

Re: ECU Pulling 5 degrees? no clue why?

Posted: Mon Nov 04, 2019 1:42 pm
by Matt
Some timing retard routines in the code, but nothing where the table is -5 degrees offset which we see here. Sorry I don't know where this is getting pulled from

It is strange that the RPM matches the warmup timing RPM max (2600rpm) but that makes no change to the operation. You may just have to map for an extra 5 degrees of timing above 2600 (to achive target timing) since it just seems to be RPM conditional (not TPS or temperature based from what I could see) and I cannot locate the code from the disassembly

Re: ECU Pulling 5 degrees? no clue why?

Posted: Wed Nov 06, 2019 1:21 pm
by my1path
Matt wrote: Mon Nov 04, 2019 1:42 pm You may just have to map for an extra 5 degrees of timing above 2600 (to achive target timing)
That approach sounds like I could make tons of mistakes

I did a short drive today on a stock ecu I bought to test it. Map tracing was not available but from what I could see in the short period I don't think there was a 5 degree drop. I downloaded the map before plugging the nistune ecu back in and I will copy the minimum needed items from my current tune to it and see how it does using a different M30 ecu as its base. (K value, timing, fuel)

Re: ECU Pulling 5 degrees? no clue why?

Posted: Thu Nov 07, 2019 11:14 am
by my1path
my1path wrote: Wed Nov 06, 2019 1:21 pm I did a short drive today on a stock ecu I bought to test it. Map tracing was not available but from what I could see in the short period I don't think there was a 5 degree drop. I downloaded the map before plugging the nistune ecu back in and I will copy the minimum needed items from my current tune to it and see how it does using a different M30 ecu as its base. (K value, timing, fuel)
Timing is still pulled using the tune I copied from an unmodified ECU. 1 of 2 possibilities here.
1 I may have been wrong, really hard to tell without proper map tracing.
2 maybe problem is hardware related.

Re: ECU Pulling 5 degrees? no clue why?

Posted: Tue Jun 09, 2020 3:21 am
by Howlermonkey
When you ground pin 44 on a fully warmed M30, it pulls 5 degrees of timing at idle (and only at idle).

But you've known this since 2012 so likely something else.

I know using the vg30 knock sensor on an old L28 will pull timing at times because it hears the noise difference from a VG30 to L28. Many old L28s will interpret mechanical noise as a knock.

I deleted it by using a resistor of super high resistence.

My L28 swap has been running 11 years now as a daily driver.

Re: ECU Pulling 5 degrees? no clue why?

Posted: Tue Jun 09, 2020 9:56 am
by my1path
Vehicle has been parked for some time but My last thoughts were the difference in KS Its a PITA to reach in the valley and I was just gonna cut the harness and see but I may be taking other directions.

Sadly sell it as my collection is getting too large (by some definition)
My unfinished supercharged v6 will got to another one of my toys and I'm thinking 300zx 84 NA ecu for this next NIstune as there are a lot more folks playing with those than M30 so it should be ironed out better...

Re: ECU Pulling 5 degrees? no clue why?

Posted: Thu Jun 11, 2020 12:48 pm
by Matt
We don't support the 1984-1985 Z31 ECU anymore. The ECU code has issues with USB consult + higher RPM commanding a stable injection time. Use a 1987-1988 VG30E (NA) ECU instead for 1984-1985 vehicles

Re: ECU Pulling 5 degrees? no clue why?

Posted: Thu Jun 11, 2020 2:08 pm
by my1path
1987-1988 VG30E (NA) Thanks, I will keep that in mind!
The donor vehicle is incompatible with nistune (another truck) so a Re-pin will happen no matter what ECU I use.