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13th August 2010, 20:13 | #1 |
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Autobox issue on ZTT CDTi
Has anyone experienced the autobox not changing up a gear when you think it should, or lift off the throttle slightly to encourage it to change up? Its as if the gear selector is set in '3' or '2' rather than 'D'
It occurs mainly in 2nd gear or occasionally 3rd and is predominently at lower speeds as you have turned at a junction or going up a slight incline. It has been an occasional thing, but is happening a little more often now, and on flat roads too. The car is five years old and I was planning a fluid change. Any thoughts? |
13th August 2010, 20:18 | #2 |
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I think fluid is due 4 Years and/or 60k so that might be a good move.
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13th August 2010, 20:25 | #3 |
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Am hoping the fluid change will sort it, was in the pipeline to do this year even before the problem started. The car has only done 35k, but I thought I should get it done on age grounds! Just wondered whether anyone else had encountered it and if a fluid change did indeed sort it?
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13th August 2010, 21:30 | #4 |
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Have encountered the same on both mine in exactly same circumstances - junction and then away up a slight hill. Normally only happens with a cold or coldish car ie when the autobox fluid is not up to working temp and when I have not had to come to a dead stand at the junction. Accelerating a bit harder up the incline makes the box change up.
I have put it down to the cold start proceedures whereby the car will hang on to lower gears more than usual until fluid is up to temp as a design feature in the autobox software. Both my cars had autobox fluid changed about 2 years ago and exibited the behaviour above both before and after. On that basis not sure if a change of fluid would help you. But as your car is 5 years old I would suggest a fluid change anyway. Fluid changes are scheduled for 60k miles or 4 years whichever sooner. |
13th August 2010, 21:45 | #5 |
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Howdee. A fluid change is always worth doing so long as it's done properly. Just had mine done and it's loads better.
As stated the cold oil will make the gears hang promoting a quicker warm up. As opposite the warm oil will make a quicker change up to increase cooling. Also don't forget our autos have tilt sensors on them so they will plum for holding lower gears on an incline or decline. A touch of the brakes on a descent will make the car select the next gear up. Both mine hang the gears occasionally. Makes you want to wiggle the selector about.
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13th August 2010, 22:02 | #6 |
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Slightly off topic but I have always wondered if there are tilt sensors since I thought the autobox worked out what to do by accelerator position, engine and road speed, amount of steady brake pressure etc.
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16th August 2010, 19:17 | #7 |
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Good to know a few other members have experienced a similar thing. I've never really noticed it on my petrol auto, but it did hold onto 2nd going down a hill when cold on Sunday! Its gearbox fluid was changed a couple of months ago. The ZT is lined up to be done in the next couple of weeks.
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