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VX 2002 n/a 3800 Auto.
While i am thinking of this topic for my future tuning.

I am not sure 100%, but am inclined to think it may have.
When coasting in a 50-70 kmph zone, the car doesn't shift in to 4th gear.
I am thinking it is settable in the Normal 1-2, 2-3, 3-4 Upshifts %TPS Vs KPH tables. But I am not too sure if I would just alter those values or rather need to be adjusting somewhere else as well?
As I am thinking the position of the TPS could vary depending on load of the engine, meaning the change of gear needing to be also linked to manifold vacuum before changing up or down the overdrive gear ?

Am I possibly overlooking another gear change setting which I need to link so that 4 gear at coasting could be engaged at say 50kmph speeds?

My car doesn't go into 4th until about 95 lightly accelerating. I don't know why you would want to it to shift so low, it will just bog down.

The earlier V6's used to go straight to 4th. later models stay in 3rd I believe and use converter lock which in my experience tends to give better economy.

I am pretty sure it used to run more down around the 1100-1200rpm, where now its more around the 1400-1500 at about 60kmph.
300 rpm to me is quite a lot more fuel consumed if not needing to be. If the motor does struggle it should kick down at those times to compensate?

Are you sure it's just not the TCC not engaging?

Mine doesn't engage until the coolant temp gets to 44ºC so I have to wait a while before the rpm drops a few 100 rpm after it's been in 4th for a while already.

1100-1200rpm is coasting down the road, I've owned multiple Commodores and never seen 1100rpm cruising down the road under load and unlike the older Buick 3800 V6 motors, the ecotec V6 is a bit of a slug at lower rpm in stock standard form.

vlad01 wrote:Are you sure it's just not the TCC not engaging?

Mine doesn't engage until the coolant temp gets to 44ºC so I have to wait a while before the rpm drops a few 100 rpm after it's been in 4th for a while already.

Good point. I have just checked last nights log. The TCC is engaging. Here are some readings of a snap shot in the log file.

ECT 85.2Deg
RPM 1555.
Road Speed 58Kmph.
Gear Ratio 1.00 (3rd gear)
TPS 5%
TCC: Engaged.
Closed Loop Mode Active.

immortality wrote:1100-1200rpm is coasting down the road, I've owned multiple Commodores and never seen 1100rpm cruising down the road under load and unlike the older Buick 3800 V6 motors, the ecotec V6 is a bit of a slug at lower rpm in stock standard form.

I don't doubt you. I am only going by what memory is and what I feel it used to be. I can be wrong, apparently I have been a few times before but not sure

I don't have another one to compare. I do know that when i initially had my car, it was very unique in how it was for things like that. I just put it down to me as a person. LOL
But I do think if I can get it to go to 4th it should be around the 1200 rpm mark, which would make my memory of it previously doing so correct.
I have also considered age and likely slippage by the trans. But from log files it shows that slippage at coast with in TCC engaged is minimal around less than 2-5kmph.

I would love to have had my original ECU tune settings before it died to compare the tune settings of today. But short of another factory unused un tuned unit to get settings from, I can only go with what I have and is available to me today and work from that.

I do appreciate all you guys feedback, support and advice. I feel I am learning lots. I just hope I can give back some help to others as time goes on.

You should be able to compare the std from a bin file on the1's Memcal data program.

Charlescrown wrote:You should be able to compare the std from a bin file on the1's Memcal data program.

To this point I have been unable to locate an original. If anyone can point me to the actual bin, that would be very helpful and appreciated.