Disco2 v8

**Scouse** · 29th January 2007, 01:24 PM

I'm pretty sure Sports mode alters the change points under hard acceleration.

The ZF boxes are pretty good for gear changes & I'm still betting it's actually being the lockup point

.

Can you do a test for me:
Cruise along at 75kph in "D" when you think it's in 3rd (as yours only goes into 4th at 80-85kph) & pull it back into "3" manually.
Do you feel it change back ?

**shory** · 29th January 2007, 01:29 PM

Originally Posted by Scouse

I'm pretty sure Sports mode alters the change points under hard acceleration.

The ZF boxes are pretty good for gear changes & I'm still betting it's actually being the lockup point

.

Can you do a test for me:
Cruise along at 75kph in "D" when you think it's in 3rd (as yours only goes into 4th at 80-85kph) & pull it back into "3" manually.
Do you feel it change back ?

I also tried that and theirs no change.
Ive also tried taking off in 3rd and shifting manually into D and still no change until i reach 80/85kms.

**ladas** · 29th January 2007, 01:44 PM

Originally Posted by Scouse

I'm pretty sure Sports mode alters the change points under hard acceleration.

The ZF boxes are pretty good for gear changes & I'm still betting it's actually being the lockup point

.

Can you do a test for me:
Cruise along at 75kph in "D" when you think it's in 3rd (as yours only goes into 4th at 80-85kph) & pull it back into "3" manually.
Do you feel it change back ?

So it could be a fault with the lock-up solenoid valve then ???

**ladas** · 29th January 2007, 01:56 PM

Or the output shaft speed sensor I guess

**shory** · 29th January 2007, 02:09 PM

Hopefully its nothing to major.
Ill try and get it in to see someone tommorow.
Thanks for all the replys

**ladas** · 29th January 2007, 02:56 PM

I have just been up the road, 4th drops in at 62 kph - just gently driving, and when I put it into sports mode it's just over 80 kph

What is your RPM at 60 and 80 - before it changes to 4th.

**shory** · 29th January 2007, 03:13 PM

RPM at 60kms with foot just on throttle is 2000 and heading up to 80kms is 2500 and still hasnt dropped.

**PhilipA** · 29th January 2007, 03:31 PM

What happens if you are doing say 70Kmh when it has not changed into Top gear, and you manually pull the gear selector back to "3"?
regards Philip A

**shory** · 29th January 2007, 03:42 PM

It doesnt do anything, But once it drops into 4th gear if i then pull back into 3rd gear then you feel it drop back.
It does change but not till over 80kms

**PhilipA** · 29th January 2007, 03:53 PM

Ah , the joys of electronics.
I think you should take it to someone with a Rovacom or Testbook and look at the faults.
I am certain that the behaviour you describe is not correct.
Lots of us here have experience with the older 4HP22 in which the changes are controlled by a kickdown cable which senses throttle position and changes the shift points accordingly. On light throttle a 4HP22 will change into 4th below 60KMH and I think the electronic version should also .
I guess that is why we all say that its the clutch locking that you can feel as it locks up at 85Kmh and is controlled AFAIK by the governor in the transmission which mechanically senses output shaft speed.
In your case the throttle position is sensed electronically from the ECU, and the road speed from the speed sensor, so it could be these sensors or some others at fault. It could be a faulty solonoid in the transmission valve body.
Regards Philip A

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