Guys gear sliping

[UAE_77]

Guys,
HOw can I fix the gear sliping? When I drive in the second gear I can fell some sliping in the gear...Is there are any way to finx it with HPT.

[jimmyblue]

Don't go by feel. Log it. Log your engine RPM, input shaft speed,
output shaft speed, TCC slip, TCC duty, Line pressure PWM%,
force motor current, trans temp, and delivered torque (engine).

I never lock the TCC in 2nd, so I could never notice any slip if it
were happening. But my logs have said, it doesn't.

If you feel slip there's a good chance (esp. with an aftermarket
converter) that the slip is in the TCC and not the transmission
clutch packs.

In my experience high trans temps aggravate TCC slip.

Oh, and another good way to pick up slip, is to mess up your MAF
and make it read low airflow; this softens up the line pressure...
so I would rethink that K&N, and give it a bath.

[UAE_77]

Thanks Jimmeyblue....
I will log the file and let you know what is going on....one more time thanks

[MNR-0]

A log of the suspect tranny-slip will tell us heaps. Just log using the default.cfg scanner settings and post either a screen shot or the log file for us to review.

One thing I have observed is that the sensation of slip can occur when you lost reaction during a gear change. At that point the dynamic compression drastically reduces and so the VCM makes compensatory changes within that shift. It seems to me like a reduction of shift pressure occurs which makes the shift take longer, or it might be abuse kicking in. Haven't logged enough PIDS yet and it only occurs with full loss of traction (TC is switched off).

[UAE_77]

MNR-0 can I have your e-mail so I can send you the log file.
Thanks brother

[UAE_77]

Guys those are the log files
[ftp]http://www.geocities.com/ali_alqaedi/Gear_Slips.zip[/ftp]

[MNR-0]

Dude,

A HP log file of each would be better. Its difficult in excel to time analyse 6800 frames in 1 window without a scroll bar.

[UAE_77]

Sure bro they are in the way.......

[jimmyblue]

I looked at these charts and I don't see any sign of trans slippage,
even at highest engine torques. The only slip is in your converter
which appears to not lock much except in 4th. I do not know what
type of converter it is, stock or not, but the input/output shaft
ratios stay very consistent up to the max torque shown and this
means no tranny clutch slip. The TCC slip drops down into noise
when it does lock, so you seem to be good there too. But in 2nd
and 3rd I saw no locking, this is how I prefer things myself. Looks
like 2nd on Holdens is no lock and 3rd lock may just be higher than
you normally cruise in 3rd (skipping up to 4th). Did gears or converter
change on this car?

[MNR-0]

There is slip in 1-2 and 2-3 upshifts. I would recommend you increase your base line pressure by 10% until the tranny logs a completed shift within the duration of your torque management taking effect.

You need more line pressure.

[UAE_77]

Ok,
So I have to go to => Transmission =>A4TCC => tcc DC VS.Line Press Vs.Trans Temp-Base.....Is that currect

[MNR-0]

No. Its not your TCC thats slipping that I can see - well - kinda. The shift is not completing in time. Increase your base shift pressure etc.

Do this:

Transmission|A4 Shift Properties|Base Shift Pressure vs Torque vs Gear
increase by 10%

Transmission|A4 Shift Properties|Desired Shift time vs Torque
decrease by 10%

Keep doing this till your shift duration completes within the torque spark retard trough. Note you risk damage to your tranny if you increase it too much. I wouldnt go more than 75% base firmness.

[jimmyblue]

I saw shifts taking 5 ticks (0.5 sec) to complete, but I didn't
see any RPM flare. So I'm not sure this is slip or just plain
laziness.Don't know what the adaptation time settings are,
though 0.5 would be high.

Some of that could be an artifact of the K&N, check if the
LTFTs have gone positive on you and maybe clean it and
substitute a paper filter. Low airflow readings = soft shifts.

[UAE_77]

Hi guys,
regarding the LTFT and the STFT they are always 0 because I run open lope. Ok so I will try to increase the base shift pressure couple times until I reach 60% just to be in the safe side. And I will let you guys know what is going on.
You guys are the best.

[UAE_77]

Guys,
Can I do this?
1. Take the base shifts pressure VS. Torque VS. Gear from other bin files?
2. How do I increase the unmbers by 10%?
Sorry my question seam silly but I don't like to do any thing untill I'm sure of how to do it.
Thanks guys

[rattle]

yes you can copy and paste from other calibrations

to increase by 10%, in the Edit Multiple Values area, click the check in front of times, now in the box put 1.1 then click commit, that will increase the selected cell or cells by 10%, 1.2 would be 20%, 1.3 would be 30% etc.....

if you wanted to reduce by 10% you would use .90, 20% use .80 etc.....

[UAE_77]

I think The sliping is gone........the car run OK now
Thanks guys for the help.