TCC Lockup Issue
Looking at my Trans logs I see that the TCC is releasing at 66 kmh in 3rd rather than 50kmh as per the tune. 65 kmh is the appropriate release speed in 4th according to my tune. This explains why the TCC is constantly locking/unlocking in 3rd. Why isn't the correct table being used?
Also seems that the TCC is locking during upshifts even though D2801 is set to "NO"??
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
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Here are the tables:
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
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Tried copying the 3rd gear TCC Release Normal column to the 4th gear table to see what would happen. No change. TCC still releases as soon as TP goes below 15%. Is there anything else that controls TCC release other than these tables? TCC throttle release tables are all at 100%.
Also noticed that the Gear PID never shows P, R or N. It shows 1st gear for all of these. Is this normal?
Last edited by DrX; December 16th, 2006 at 11:41 AM.
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
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DrX,
PCM unlocks the TCC if misfires are detected...
But make sure the TCC release tables have a lower speed than the corresponding apply tables.
The 2nd chart images shows the TCC DC going down during the shift and never coming back up to 95+% even tho TCCMODE shows locked.
And the GEAR pid should show the actual gears as 1st, 2nd, 3rd, 4th (and not the gear selector/lever position); there maybe an alternate GEAR pid for this, check your list of PIDS.
Hmmmm.... you have something strange going on.
Joe
I never log any misfires. Unlock is always around 68 kmh when the throttle is below 15%.Originally Posted by joecar
TCC DC is always lowest in the logs when the TC is "Locked" and high when "Enabled".
Couldn't find any other "Gear" PID. 1,2,3 and 4 are indicated correctly. P, R and N are not. The gear selector position PID works properly.
Yes, Release tables are all lower than Apply tables. Going to try a copy and paste of the factory TCC tables today just to see what happens.
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
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What gear is the selector in? D or 3? The random locking/unlocking is pretty common on cammed LS1's and those with high stall converters, but I am not quite sure if thats the case on yours. You could try increasing the values in the C5622, C5623, C5625, and C5626 tables and see if that helps.
Selector is in D when driving. When in P, R, or N the Gear PID shows 1st. Dug up some old logs and it was the same. Does anyone see P, R, or N in their logs?
No cam here, 2600 stall. I'll check those tables. Seems to me that I already maxed them out, that's why I am not logging any misfires.
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
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Misfire tables were already back to stock. But I do recall maxing them out before as an experiment. Didn't have any effect on anything. I logged the misfire PIDS last week and didn't see anything using the current/stock tables.
Tried the factory TCC Apply/Release tables today which are a little lower. The TCC still releases in 3rd at any speed when I let off the throttle. Looks like it doesn't release until TP falls to 10% though. Previously it was releasing around 15%. The release speed in the table is 40kmh for TP values of 0-25%.
It is interesting that there is a "Coast" mode for the TCC in 4th but not in 3rd. Also looks like TCC DC% is high until full lockup and responds to slip during lockup. It is also higher when holding Lock in 4th than in 3rd. Here are a few snapshots from todays log to illustrate:
Here's the log file:
Last edited by DrX; December 17th, 2006 at 05:27 PM.
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
Gettin' the Groceries
Hmmm....
TCCDC seems to rise until TCCSLIP goes to zero... and then it went down...!!!
I was taught that TCCDC typically stays at 97+% when TCC is locked.
Are your D1008 and D1009 set to 100% all across...?
Yes.
2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
Gettin' the Groceries
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