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View Full Version : Can Nanocom or other Diag unit change parameters in TD5 auto?



bruiser69
23rd December 2008, 03:45 PM
I was wondering if Nanocom or other diagnostic unit can interrogate/ reprogram ECU controlling ZF auto box used with TD5. Anyone Know?
ZF auto doesn't lock up converter until approx 85KPH (2000Rpm). As majority of my driving is on major roads with 80KPH limit, I would save a lot of fuel if I could get lockup to occur at a few K below 80. As torque curve is basically flat from 1500RPM I can't see lowering lockup speed would cause any issues.

Cheers..Bruiser

Tombie
23rd December 2008, 10:55 PM
Take the selector out of D and use it in 3... :cool:

Fuel saving will be nothing at 80km/h anyhow.

Ricey
24th December 2008, 05:50 AM
Nanocom doesn't have that faciility. What sort of figures are you getting?

bruiser69
24th December 2008, 08:36 AM
Nanocom doesn't have that faciility. What sort of figures are you getting?

Hi,
I do 70K return trip to work every day & average approx 11.5 litres per 100K.
Most of this run is at 80K. On highway, with cruise control set to 100KPH I average 9.5.
Motor is standard (no chip) with 170K on clock.

Cheers..Bruiser

PhilipA
24th December 2008, 09:00 AM
I have a theory as to why the lockup is at 85Kmh, as it does this in a RRC V8, Disco V8 and as you say in your TD5 Disco.

In my RRC V8 the fuel cuts on overrun over approx 1500RPM and then is resumed under 1500RPM. I am assuming the TD5 does the same.

This relates to about 80KMH in my RRC in 4th and the gearing is similar in a TD5.
In an RRC I think they do the lockup at 85Kmh to avoid a large jerk if the fuel resumed at 1500RPM on overrun and the converter was locked as the rev difference between fuel cut off engaged and resumed is a couple of hundred revs cushioned by the TC.
If you had TC lockup the jerk would be quite significant and probably have people back at their dealers complaining.
Regards Philip A

JohnF
24th December 2008, 09:29 AM
I have a theory as to why the lockup is at 85Kmh, as it does this in a RRC V8, Disco V8 and as you say in your TD5 Disco.

In my RRC V8 the fuel cuts on overrun over approx 1500RPM and then is resumed under 1500RPM. I am assuming the TD5 does the same.

This relates to about 80KMH in my RRC in 4th and the gearing is similar in a TD5.
In an RRC I think they do the lockup at 85Kmh to avoid a large jerk if the fuel resumed at 1500RPM on overrun and the converter was locked as the rev difference between fuel cut off engaged and resumed is a couple of hundred revs cushioned by the TC.
If you had TC lockup the jerk would be quite significant and probably have people back at their dealers complaining.
Regards Philip A

Phillip as much of my windy road driving, around 80km per day, 4 days a week is done at around 80km per hour, I find it very frustrating. I have a 1990 RRC. Is it posible to change this, so she locks up at a different speed. what is most economical.

PhilipA
24th December 2008, 09:45 AM
Well, the 2HP22 in a 3.5 Range Rover AFAIR locked up at 76Kmh, so there should be parts available (governor?) to enable the same on a 4HP22.
There was some discussion on this about a month ago where someone enable lockup in 3rd.
I guess the trick is to find the auto shop who knows how to do it.

But as I said you may not like the resulting jerking as AFAIR the 3.5 does not have overrun fuel shutoff and it is probably the reason they changed the speed for lockup into 3.9 and subsequent .
ASHTRANS where are you when we need you???
Regards Philip A

Slunnie
24th December 2008, 10:07 AM
The Disco2 does lockup in 3rd which is also what Tombie2 is saying.

harlie
5th January 2009, 01:37 PM
I have a theory as to why the lockup is at 85Kmh, as it does this in a RRC V8, Disco V8 and as you say in your TD5 Disco.

In my RRC V8 the fuel cuts on overrun over approx 1500RPM and then is resumed under 1500RPM. I am assuming the TD5 does the same.

This relates to about 80KMH in my RRC in 4th and the gearing is similar in a TD5.
In an RRC I think they do the lockup at 85Kmh to avoid a large jerk if the fuel resumed at 1500RPM on overrun and the converter was locked as the rev difference between fuel cut off engaged and resumed is a couple of hundred revs cushioned by the TC.
If you had TC lockup the jerk would be quite significant and probably have people back at their dealers complaining.
Regards Philip A

The D2 (my TD5) will lock up in 3rd and keep it locked down to about 45kmh - and there is no jerking... If this fuel cut off causes a jerking why is it not a problem in the manual vehicles?

I too would like to have the TC lock up earlier, from 70-80kmh it won't pull skin of custard. Mine locks in at 80-82 and with the right foot in the same spot it just rockets away. So pedal in same position, engine ECU feeding same fuel (well MAF reading same) = huge increase in acceleration once TC locks in - can't tell me lock up is NOT better on fuel... I think Tombie would be right, lock up in 3rd would be better than D without lock. You could soon check with Nanocom - get throttle pos readings along same road section in different gear each time.

Question - the lock up solenoid is controlled by the Trans ECU. So this would need to be a parameter change in the ECU? Has anyone played with this? I’ve asked around about this a couple years ago and could not find anyone...
Come on B.A.S. (Pete) what you got for us....