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Old Jun 29, 2003 | 12:55 AM
  #1  
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Default Lost timing

For some reason I'm not getting full timing. It seems MAX KR vs. RPM value ( 4 ) is always substracted from timing curve values even though ATAP says KR is zero. It's not on low octane map, the timing values would be even lower.

Car is a -98 Z28. MAF table and base spark tables are stock. I've tuned ltrims using infector flow rate.

What should I look into ?
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Old Sep 6, 2003 | 12:19 AM
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Default Re: Lost timing

i'm having the same problem but intermittentlty.
mine is a 99.
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Old Sep 6, 2003 | 01:03 AM
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Default Re: Lost timing

For some reason I'm not getting full timing. It seems MAX KR vs. RPM value ( 4 ) is always substracted from timing curve values even though ATAP says KR is zero. It's not on low octane map, the timing values would be even lower.

Car is a -98 Z28. MAF table and base spark tables are stock. I've tuned ltrims using infector flow rate.

What should I look into ?
What intake air temps and engine coolant temps are you running at??? Is this at all RPMs and gm/cyl ???
joel
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Old Sep 6, 2003 | 04:26 AM
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Default Re: Lost timing

i was tinkering around in ls1edit and noticed that one of the torque manegement tables was not zeroed ( the one with the smooth increasing curve - exponential), so i flattened it out so it reads all zeros, and what do you know! i'm getting my timing where i want it!

i also returned the kr tables back to stock , except for the max kr vs. rpm ( i think that's what its called) where i made the max kr 4 deg. across the board.
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Old Sep 6, 2003 | 10:32 AM
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Default Re: Lost timing

i was tinkering around in ls1edit and noticed that one of the torque manegement tables was not zeroed ( the one with the smooth increasing curve - exponential), so i flattened it out so it reads all zeros, and what do you know! i'm getting my timing where i want it!

i also returned the kr tables back to stock , except for the max kr vs. rpm ( i think that's what its called) where i made the max kr 4 deg. across the board.
A4 I assume-congrats!!! What is yours pekkaz A4 or M6??
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Old Sep 6, 2003 | 12:12 PM
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Default Re: Lost timing

no , i have an m6.

why did you assume i had an A4? do they have different torque management characteristics??
is the procedure done differently in an A4?
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Old Sep 6, 2003 | 12:34 PM
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Default Re: Lost timing

From what I've read here,and on other sites, there is minimal interaction between TQ MNGMT and the rest of the PCM with an M6 (M12). With an A4 it's suggested that all tables in TQ Management be "Zeroed Out". Whereas with standard transmissions I,ve read that we need only change Max Tq setting to 639 and set Abuse Mode Test to an unrealistic RPM. This definitely doesn't jibe with your experience.
Was TQ Mngmt pulling timing at high loads and high RPM?
MAYBE ONE OF THE gurus will chime in?????
joel
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Old Sep 6, 2003 | 02:29 PM
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Default Re: Lost timing

from what i`ve heard some m6s use the tq management to pull timing when you shift to reduce the chance of detonation from the load change and smooth the shifts.
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Old Sep 7, 2003 | 01:05 AM
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Default Re: Lost timing

The car is A4. Sorry, I haven't looked into this issue for a month or so and forgot this thread. Piston slap is getting worse and I'm pulling the engine within couple of weeks.

I was not logging the IAT or engine temp, I've zeroed ignition IAT-MAP table. The engine was operating at normal temps according to the gauge.

Max torque is set 500 and I've zeroed upshift torque reduction from 275 and up. Abuse mode torque reduction is zeroed. Abuse mode test is rpm > 7000, speed < 0. TCS retard tables are stock. Torque loss from retard is stock as I wanted to keep some of it for mid throttle shifts and get control through the upshift table.

Thanks for the suggestions. I'll have to come back to this during next spring. Driving season here in Finland is soon over.


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Old Sep 7, 2003 | 04:37 AM
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Default Re: Lost timing

well it's official , i have my timing back .
i floored it a few times tonight and all of them were with in my timing table except if i had knock.
i'll keep fooling around with this for next few days since the driving season in AZ never stops (gets better in winter), i'll keep you guys posted.
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