Tune issue - power killed when hitting 2nd gear

[Andy13186]

I got a PBD tune and it seems good other than 1 issue, when I have advancetrac fully disabled but shift from 1st to 2nd (paddle shifting usually) and break traction , it kills power for a few seconds and I cant accelerate. It almost feels like traction control but its fully disabled and the traction control light doesnt come on. Anyone ever experience this or know of a solution? Tuner thinks its something transmission related.

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[growler]

its bumping rev limiter when tires break loose

 

[ugstang17]

Shift earlier. The paddle shift (hate that term) has a delay due to the fluid mechanics that is common in many auto transmissions. In drive the shift is commanded early so that it occurs at the desired RPM. This is why auto's (especially on higher HP setups) require more revisions to get dialed in....aside from proper shifting firmness and minimized flare. This is another reason I am looking to go back to a stick shift.

If you take the time to datalog and view the shift command verses when you see the RPM drop going into the commanded gear you will see the delay.

 

[Myshelby3425]

I get that small pop during my shifts at partial throttle in the lower gears. Rob said it had to do with a change in the timing tables. I didn’t get it on my Lund tune, but I did pick up 10whp switching to PBD.

 

[ugstang17]

^^^^ The change in timing at lighter throttle should not effect your peak HP number. So datalog it and send it back to him and see about a revision.

 

[Andy13186]

its bumping rev limiter when tires break loose

Shift earlier. The paddle shift (hate that term) has a delay due to the fluid mechanics that is common in many auto transmissions. In drive the shift is commanded early so that it occurs at the desired RPM. This is why auto's (especially on higher HP setups) require more revisions to get dialed in....aside from proper shifting firmness and minimized flare. This is another reason I am looking to go back to a stick shift.

If you take the time to datalog and view the shift command verses when you see the RPM drop going into the commanded gear you will see the delay.

Its not hitting the rev limiter, I can see the log in VCM scanner I am no where near the rev limiter I shifted at 7500 my rev limiter is 8200.

Trevor at pbd is doing mine.

https://www.dropbox.com/s/rh99udgo64k46w2/log0027.csv?dl=0

There is a datalog of the issue happening ^

 

[ugstang17]

Don't see anything that sticks out. Would have liked to seen the actual ETC v desired ETC position once you punched it and went WOT @ 6000 RPM, (no data visable in that column) but aside from that I see nothing. You're in Florida, it can't be that far to take it to them one day and have them work through it with you (for me it would be a 2 day drive one way). Otherwise reload the factory tune and take it to the dealer to have the 10 speed auto checked out. I just keep finding more an more reasons to go back to a stick shift car.

 

[Andy13186]

Don't see anything that sticks out. Would have liked to seen the actual ETC v desired ETC position once you punched it and went WOT @ 6000 RPM, (no data visable in that column) but aside from that I see nothing. You're in Florida, it can't be that far to take it to them one day and have them work through it with you (for me it would be a 2 day drive one way). Otherwise reload the factory tune and take it to the dealer to have the 10 speed auto checked out. I just keep finding more an more reasons to go back to a stick shift car.

Thanks for looking. Do you have a vcm scanner layout that I could download?

 

[ugstang17]

No I don't think I do. I use live link II. SCT's software package to datalog through and that is it. If the file is an excel spreadsheet I that live link recognizes I may be able to see it through that come to think of it.

 

[ugstang17]

I would need the actual file though.

 

[Zinc03svt]

These cars have buried limiters. Keep working with your tuning to sort out. I had it on my 2-3 and 6-7.

 

[Dusten]

Others have posted the data here, the motor has a ton of limiters based on temps, load and other things. It could be smacking a limter he didn't change

 

[ugstang17]

Others have posted the data here, the FACTORY TUNE has a ton of limiters based on temps, load and other things. It could be smacking a limter he didn't change

Corrected that for you. I'm sure you meant to say Factory Tune not the engine. The engines get enough bum rap in threads without having to shoulder the blame of tune in the ECM as well.

 

[armykyle1 [HACKED ACCOUNT]

Do you have drive modes? Are you running it in any particular drive mode when it happens? I think I might be having a similar issue when I'm in drag mode. I was doing a log and on the second pull, I bumped it into drive and the following shifts were all jacked up. No wheel spin but I did have advanced track on.

I have a feeling it won't do it when it's sport mode. I won't have time to find out until Friday unfortunately.

 

[Andy13186]

Do you have drive modes? Are you running it in any particular drive mode when it happens? I think I might be having a similar issue when I'm in drag mode. I was doing a log and on the second pull, I bumped it into drive and the following shifts were all jacked up. No wheel spin but I did have advanced track on.

I have a feeling it won't do it when it's sport mode. I won't have time to find out until Friday unfortunately.

Yes I have the modes. It does it in sport mode, and drag mode while the shifter is in S and I am paddle shifting (probably does it in all the modes). Not sure if it does it in drive, I paddle shift about 99% of the time and that requires sport mode so id like it to work well in sport mode. The 75%+ throttle shifts in sport mode are a bit too firm in my opinion too currently, they feel like dragstrip mode now basically. I am trying to get my tuner to smooth them out a bit for sport mode. I loved the stock tunes 3-4 gear and up shifts in sport mode they were seamless. The 1-2-3 were not good though the stock tune pulled timing hard on those to keep traction I think.

These cars have so many mode combos it must be hard to tune.

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