joecar help!

[SRT10KLLR]

joecar, can you help me help myself? I want to understand how the TCC apply release works so I can make adjustments. After my high stall went in I was getting some shuttering while coasting to a stop. I increased the apply/release and it helped but it does not always lock/unlock when it is supposed to. Also, I was looking at some logs I made and the tcc does not lock after a long idle(waiting for a signal light) even if is meets the criteria.

BTW, I drove around for a week with the DR's on because I was to lazy to put my street tires back on and I love the way the TCC locks/unlocks and don't know why it acts differently. The only thing I can see is that the RPM's are higher with the DR's because the smaller diameter(28" vs 31").

[DrkPhx]

A 3" difference in tire height can significantly alter the shift points and TC lock/unlocking.
First you need to adjust to the correct tire height. The shuddering on decel sounds like the TC is not unlocking. You need to raise the TCC mph release value so it unlocks sooner. Raising the values in the misfire table also will help with the random lock/unlocking of the TC.

[SRT10KLLR]

A 3" difference in tire height can significantly alter the shift points and TC lock/unlocking.
First you need to adjust to the correct tire height. The shuddering on decel sounds like the TC is not unlocking. You need to raise the TCC mph release value so it unlocks sooner. Raising the values in the misfire table also will help with the random lock/unlocking of the TC.

I adjusted for the tire but only H0101 and H0104. I did not allow the program to automatically make shift point corrections.

To try and get rid of the shuttering I increased the TCC App/Rel speeds but it only shifter the problem to a higher speed. I then closed the gap between them so there is only a 2 mph diff and that helped a lot because now it unlocks before any shutter happens.

The values in all the misfire tables have been increased from 43-80% but I am still getting an occasional code here and there.


I am trying to understand what is happening with my tranny because going back and looking at my logs I have noticed that sometimes I will meet all criteria for a lock or unlock but it will not happen. I like when it unlocks as soon as I get into it to overtake another vehicle or while climbing a hill otherwise it has no power or I have to give it enough gas to warrant a downshift. I noticed that after a long idle like waiting for a signal light it will not lock the TCC until I have driven it for a long time.

The more I can understand how it works the better I will be able to make adjustments. Thanks for your input, I really appreciate it.

[DrkPhx]

I adjusted for the tire but only H0101 and H0104. I did not allow the program to automatically make shift point corrections.

Good. I tried that once and it f-ed all of the shift points.

To try and get rid of the shuttering I increased the TCC App/Rel speeds but it only shifter the problem to a higher speed. I then closed the gap between them so there is only a 2 mph diff and that helped a lot because now it unlocks before any shutter happens.

Sounds like you got it figured out. It seems each converter and car is different. In the 0-25% TPS cells I have my 4th gear TCC release values set much higher than the same cells in the TCC Apply table. If you still get the shuddering on decel with 0% TPS, raise the specific cell much higher.

The values in all the misfire tables have been increased from 43-80% but I am still getting an occasional code here and there.

Check the freeze frame data when the code is set again. This wll give the exact operating conditions logged at the time the DTC was set. As a test, increase all values in all cells to the max allowed and see if that helps.

I like when it unlocks as soon as I get into it to overtake another vehicle or while climbing a hill otherwise it has no power or I have to give it enough gas to warrant a downshift

This is how it should work. It took me countless hours and datalogging to get that part correct. If the TCC does not release as soon as the car climbs an incline, then you still need to tweak the tables further. I would also disable TCC Apply in 3rd gear. Most big converter seem to have problems with that.

I noticed that after a long idle like waiting for a signal light it will not lock the TCC until I have driven it for a long time.

That's unusual and it shouldn't matter. Once again try maxing out the values on the misfire table.

[joecar]

I am sorry I must have missed this thread somehow...

When you swap the stock TC (bigger, heavier) with a stall TC (smaller, lighter), you have reduced the engine rotating mass/inertia... this may affect the misfire detection (it won't be right)... so you may also need to do a CASE relearn.

Yes the shuddering means it's not unlocking and is grabbing/slipping/jumping in rapid succession, engine wants to lug, vehicle's mass/inertia won't allow, so TCC shudders... do what DrkPhx said, don't allow locking in the low cells.

+1 check the freeze frame data when you get a code.

[SRT10KLLR]

Good. I tried that once and it f-ed all of the shift points.

Yes, I did not want it messing with my settings since I liked them right where they were.

Sounds like you got it figured out. It seems each converter and car is different. In the 0-25% TPS cells I have my 4th gear TCC release values set much higher than the same cells in the TCC Apply table. If you still get the shuddering on decel with 0% TPS, raise the specific cell much higher.

Is that so it will not lock at 0-25% TPS? I have my first two cells both set to 256 mph so it won't lock at those low TPS values either but I noticed that I never hit those cells. I think it it because I have a ETC because even off the throttle I am still seeing like 12% from the TPS. My TC just doesn't like low rpm/speed while locked that is why it was shuttering. Since raising the cells I have only seen it once although now if driving right at the mph for lock/unlock it will fluctuate between the two modes unless I slow down or speed up which sometimes I can't do to traffic.

Check the freeze frame data when the code is set again. This wll give the exact operating conditions logged at the time the DTC was set. As a test, increase all values in all cells to the max allowed and see if that helps.

Unfortunately, every time I log it has not done it. Then I will not hook up the laptop and bam there it is, lol. It is like when you go to the doctor or mechanic with certain symptoms but when you get there you can't duplicated them. The misfire counts were maxed out once by a local shop/tuner but I did not want that because if I ever have a real misfire I will not know it.

This is how it should work. It took me countless hours and datalogging to get that part correct. If the TCC does not release as soon as the car climbs an incline, then you still need to tweak the tables further. I would also disable TCC Apply in 3rd gear. Most big converter seem to have problems with that.

The funny thing is it does it if I have the DR's on but not with the street tires. I am certain it has to do with the speeds/rpm so I will continue adjusting it.

That's unusual and it shouldn't matter. Once again try maxing out the values on the misfire table.

Yes, I have read that a certain amount of misfires renders your TCC inoperable. It goes back to its usual lock/unlock after some more constant driving.


Answer the following for me if you can.

TCC Apply Speeds in Fourth:

TPS%.....Speed
12.50 ____ 43
18.75 ____ 47
25.00 ____ 52
31.25 ____ 58
37.50 ____ 65

TCC Release Speeds in Fourth:

TPS%.....Speed
12.50 ____ 41
18.75 ____ 45
25.00 ____ 49
31.25 ____ 55
37.50 ____ 58

Given the above parameters will my TCC unlock?

Scenario 1:

I am driving on the highway with the TCC locked at a constant 60 mph with a TPS of 25% and I let off the gas on the off-ramp to coast to a stop at the light. When I let off the gas my TPS goes to 12% and I slowly begin to reduce my speed. Since my TPS is now in the 12.50% cell then the TCC should release at 41 mph, right?


Scenario 2:

I am driving on the highway with the TCC locked at a constant 60 mph with a TPS of 25% and I give it gas to overtake another car. In giving it gas the TPS goes to 37% and I begin to accelerate. Since my TPS is now in the 37.50% cell then should the TCC release immediately because I am going slower than 65 mph(the speed at which I meet the 37.5 criteria) or should it stay locked since I have not met the TCC release speed of 58 mph?

[SRT10KLLR]

I am sorry I must have missed this thread somehow...

When you swap the stock TC (bigger, heavier) with a stall TC (smaller, lighter), you have reduced the engine rotating mass/inertia... this may affect the misfire detection (it won't be right)... so you may also need to do a CASE relearn.

Yes the shuddering means it's not unlocking and is grabbing/slipping/jumping in rapid succession, engine wants to lug, vehicle's mass/inertia won't allow, so TCC shudders... do what DrkPhx said, don't allow locking in the low cells.

+1 check the freeze frame data when you get a code.

Joe, I don't know if the new stall weighed more but it was the same size. It is only a 2600 stall from Edge Racing. We did a CASE relearn when we first installed the 408 and TC.

I already have the first two rows set at 256 mph but again I don't hit those cells because the TPS never goes lower than like 10%.
Should I do the same to the next two rows also? Should I be seeing lower than 10% TPS in my ETC auto?

[joecar]

I'm at a loss when it comes to ETC... sorry.

[SRT10KLLR]

Can you answer scenario #2 from post #6?

[joecar]

Scenario 1: correct, operating point crosses the release curve [downwardly at 12.5%/41mph, so it should release at 41/40 mph... but see comment below.

Scenario 2: it should stay applied since the operating point has not crossed the release curve [downwardly] at 37.5%/58mph... but see comment below.

Comment: I have seen some controllers release the TCC on coast (throttle release) regardless of the TCC release curve... typically non Corvette/Camaro/Firebird... there may be some missing tables, or it may be a function of the hardware.