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[cam.in.head]

Just a thought .ive never been happy with the revs thats my 2003 2.6 changes at.when i bought it the revs went up to almost 4k before changing. And driving up roads at 30mph stayed in 3rd most of the time. I purchased a used gearbox ecu to try. Much better so after reading on here it seems my new ecu could be an original software version and my original was an updated one. However even though its better its still not a patch on my brothers 2.5 that changes up nice and early how i like it. Nearly as good as the old 3 speed gm in my carlton 2.2 which is purely hydraulic not electronic.so .my question is ? ?. What would happen if i fitted a different ecu ,say from a 2.2 or 3.2  or even a 2.5 .would it actually work or would it throw any codes . Or are there anywhere that can do custom maps .i drive the car as a cruiser and never rev it above 4k max .yes i know what your thinking. !. Put my bl,,,,y foot down and see its potential but each to their own! .

[Doctor Gollum]

Gearbox has a learning element. Drive it the same as theothers and it should shift the same

[cam.in.head]

Yeah thats what i heard. I beleive that dissconnecting battery starts this again from scatch? Is that true ?

[Doctor Gollum]

Should do the trick, but leave it off a while to be sure

[cam.in.head]

obviously when i put on the replacement ecu thats was starting from scratch but would any of the other ideas work. i realise its working correctly and not faulty as such.but was hoping of some way of getting a lower rev change up . think this makes sence !

[Doctor Gollum]

Not in sports mode?

[Andy H]

Fit a manual gearbox?

[cam.in.head]

no. never use it. tried it and it makes it change much higher. i dont think theres a problem. all gears work ok ,smooth changes,etc i think its probably because im used to the carlton box although was driving the 2.5 this weekend and it definately changes up sooner . would any other ecu work ?

[cam.in.head]

Fit a manual gearbox?

.                   yeah . a manual box with taxi driver changes !

[Doctor Gollum]

Swapping box ecus willy nilly will change nothing. Try driving it with a lighter right foot.

[cam.in.head]

if i drive with any lighter right foot the car will not move !. .thanks anyway

[Kevin Wood]

It's a price you pay for not having to reach for that pesky lever thing or confuse over (number of pedals > number of feet).

They can be mapped, in theory, but there's not much call for it, so nobody offers the service. Your options are probably either putting up with it or going manual.

[TheBoy]

Don't worry about the learning too much, as its only on recent miles, not over the period of days or 100s of miles.

Is this only when cold?  They are designed to hang on to gears much longer for the first minute of so to heat the cats.

The 2.6/3.2 TCM is a poor relation to the earlier (but post 1998) 2.5/3.0 TCM, which got more refinements as time went on than the 2.6/3.2 ones.

Fitting a "correct" TCM but with "wrong" configuration will likely lead to nothing but limps and other oddities.  Fitting the "wrong" TCM simply wont work.


3rd gear at 30mph sounds right to me.  Remember the ar25/ar35 is long geared to make up for lack of ratios. 4th with TC lockup would be labouring it.

[cam.in.head]

thanks mr stiltskin. yes as i said i realise theres nothing actually wrong with it technically and 3rd gear at 30mph is most likely done as its the most economical gear for that speed.the 2.5 as you mention does seem more superior but as i cant fit a 2.5 ecu and expect it to work correctly i was just testing the water and pondering any alternative solutions.on the earlier gm 3 speed non electronic boxes they changed up realy fast and could be made to change up straight away by just letting back on the throttle a bit.i have a 2.2 engine with 2.2 torque converter and box fitted to my cav and it changes up realy early probably due to the fact that it thinks its pulling a heavier carlton along.

[Andy B]

.......

They can be mapped, in theory, but there's not much call for it, so nobody offers the service. Your options are probably either putting up with it or going manual.

There was a Vauxall software update for the gearbox. ....... I had it applied to my car by Dr Omega many many moons ago .... no idea now what version it was

[TheBoy]

.......

They can be mapped, in theory, but there's not much call for it, so nobody offers the service. Your options are probably either putting up with it or going manual.

There was a Vauxall software update for the gearbox. ....... I had it applied to my car by Dr Omega many many moons ago .... no idea now what version it was

Yours was a MFL 3.0l IIRC, so had a GS820 TCM, which can take the v9 firmware via Tech2, that's actually pretty good

[Andy B]

Yours was a MFL 3.0l IIRC, so had a GS820 TCM, which can take the v9 firmware via Tech2, that's actually pretty good

That sounds about right 

[ronnyd]

My Desmond sometimes does the same thing, even when warmed up. Go gently on the pedal but still wants to rev hard. All other changes are smooth and normal. Fluid level and condition all good.

[TheBoy]

For 2.6 owners, I know our resident pikey pensioner, Mr Auto Addict, had a problem with his hanging on to gears in a specific circumstance that I can no longer remember.

After weeks of tell him it wasn't an ECU fault, I gave him another TCM ECU, and that cured it.


Perhaps AA can elaborate if he reads this?

[cam.in.head]

on the gm 3 speed the change points are advanced or retarded depending on engine load measured by a vacuum modulator can on the rear of the box as well as engine speed vs road speed.am i correct in thinking the omega is purely electronic working on these factors.engine speed,throttle position,road speed ,does the box also have a tilt sensor ?.

[TheBoy]

on the gm 3 speed the change points are advanced or retarded depending on engine load measured by a vacuum modulator can on the rear of the box as well as engine speed vs road speed.am i correct in thinking the omega is purely electronic working on these factors.engine speed,throttle position,road speed ,does the box also have a tilt sensor ?.

Yes, all electronically controlled by the TCM, giving it far more intelligence and control that the mechanical ones.

[cam.in.head]

does it have a tilt sensor so it knows the car is going uphill or down or purely electrical? .sorry if your last post actually answered that !

[Andy H]

For 2.6 owners, I know our resident pikey pensioner, Mr Auto Addict, had a problem with his hanging on to gears in a specific circumstance that I can no longer remember.

After weeks of tell him it wasn't an ECU fault, I gave him another TCM ECU, and that cured it.


Perhaps AA can elaborate if he reads this?

There is one set of lights, that I get held at every day on the way home from work, where the road is slightly uphill afterwards. If I am stuck behind a dawdler that insists on drifting along at 20-25 mph over the next 200 yds my 2.6 will hang on to a gear and keep revving. (I think it will hit 4000 rpm at just under 30 without much throttle but I may be wrong about that) Give it a bit more throttle and it revs harder, give it a lot more throttle and it changes up and peace is restored.

The other change point that annoys me is slightly below 50mph. The engine is just getting 'on cam' when it is dumped into a higher gear and I have to press harder to maintain the same forward progress (at which point it changes down again and the cycle repeats.........)

[Kevin Wood]

Yep, even the 3.2 bogs down horribly in the 45-50 MPH region. I think it's the torque converter lockup.

[cam.in.head]

when i got mine it held up to 4k before changing replacement ecu gives 3k so one is definately different programm wise.i guess its a trait of the car that we have to live with .i was thinking if you could alter tilt sensor if there is one but maybee not. it is frustrating thou isnt it.

[VXL V6]

2.6 Auto's do seem to hang onto the low gears I've found.

3.2 exactly as Kevin says has a horrid 45 - 50 dead zone not helped by indecision of the ECU to drop a gear when you try and gently accelerate out of the speed range, find this typically through motorway roadworks on a slight incline. Seems to be worse on one of my 3.2's for some strange reason (all running latest version of software) so maybe more down to gearbox.

[Entwood]

2.6 Auto's do seem to hang onto the low gears I've found.

3.2 exactly as Kevin says has a horrid 45 - 50 dead zone not helped by indecision of the ECU to drop a gear when you try and gently accelerate out of the speed range, find this typically through motorway roadworks on a slight incline. Seems to be worse on one of my 3.2's for some strange reason (all running latest version of software) so maybe more down to gearbox.

Easy with the 3.2... if doing 45 and you wish to avoid the "dead zone" simply press the sports button, then when you get to 55 press it again ...

[VXL V6]

2.6 Auto's do seem to hang onto the low gears I've found.

3.2 exactly as Kevin says has a horrid 45 - 50 dead zone not helped by indecision of the ECU to drop a gear when you try and gently accelerate out of the speed range, find this typically through motorway roadworks on a slight incline. Seems to be worse on one of my 3.2's for some strange reason (all running latest version of software) so maybe more down to gearbox.

Easy with the 3.2... if doing 45 and you wish to avoid the "dead zone" simply press the sports button, then when you get to 55 press it again ...

Not really, I don't want to drive the 20 miles through the road works down the M5 (when I have to actually go in the office!) in sports mode stuck in third gear and 55 is definitely in the points zone through the cameras! 

As I say, it does seem to differ across different 3.2's all have regular ATF changes and all run the last software release.

[New POD]

2.6 Auto's do seem to hang onto the low gears I've found.

3.2 exactly as Kevin says has a horrid 45 - 50 dead zone not helped by indecision of the ECU to drop a gear when you try and gently accelerate out of the speed range, find this typically through motorway roadworks on a slight incline. Seems to be worse on one of my 3.2's for some strange reason (all running latest version of software) so maybe more down to gearbox.

I have a 3.2 and in this zone I have learnt to only change speed by using the cruise one click at a time, if I don't want kick down, but even in cruise at 50 if you encounter a slight incline, it looses a couple or 3 MPH. realises, then gives acceleration, which causes it to kick down and accelerate past 50 mph, then it slows back down to 50 mph

Every Monday morning on the A50 east bound on the approach to the Meir Tunnel. 

[johnnydog]

I have two 2.6's, and 2 3.2's. Whether it's just coincidence, but both the 2.6 's seem to hang onto the lower gears a lot more than both 3.2's, particularly first / second.

[cam.in.head]

i guess its something that we will have to live with as its how it was designed rather than a fault. would be nice if there was an adjustment or mod that would overcome this aside from changing car for a 2.5 or fitting a manual box.i was hoping if there was a tilt sensor that could have been modded to fool the ecu but thanks for everyones responces. cheers