Autobox not disengaging.

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missfixit70
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Re: Autobox not disengaging.

Post by missfixit70 » Thu Nov 12, 2009 6:20 pm

Alex86 wrote:My Gearbox does exactly the same! only when cold??? i have to pop in to "N" at every junction until its warmed up then its fine for the rest of the day! it only started after i had atf changed in the summer. since then the oil has been again but its still the same. I've left it for a couple of months because of money(lack of) but hope to get it sorted before Christmas!

I'll let you know if i have any development.

Alex
When the ATF was changed, was the bottom of the gear box dropped & filter cleaned out?
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thedogsbollox
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Re: Autobox not disengaging.

Post by thedogsbollox » Thu Nov 19, 2009 6:32 pm

dandywarhol wrote:When it happens again, quickly knock it into neutral and see if the revs are "hanging up" Could be a problem with the fuel pump high idle system staying on too long - its operated by vacuum from the brake servo pump via the actuator next to the EGR actuator and triggered by the coolant temp switch in the middle of the head (which also controls the autobox warm up system)
that sounds like a goer there. Garage checked condition and level of fluid but it never done it for them of course. As soon as I go off this morning the it did it. I put in N and the revs were up alright. Nearly 1000 at idle. Normally at 750. I tried flicking the throttle to see if it would knock it down but no.
So maybe the sensor or servo or vaccuum leak.
thedogsbollox
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Re: Autobox not disengaging.

Post by thedogsbollox » Mon Nov 23, 2009 3:26 pm

This is getting even more weird.
Today it never done it for a while. Just after starting the idle revs were up again, which i presume is normal for starting from cold. I drive very easily till it gets warmed up now. Whilst driving, after about 2 mile i can feel it happening again as i approach a roundabout and i put in "N" revs still high. Gets into sainsbury's carpark and when in reverse it moves off slowly,creeping that is on idle, then shoots off like it has engaged a second reverse locked in gear.
Any more ideas guys. I am in Ireland at the mo and will take it to the garage when i get back next week, but i think they are scratching their heads too.
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dandywarhol
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Re: Autobox not disengaging.

Post by dandywarhol » Mon Nov 23, 2009 3:45 pm

This could be a torque convertor problem as nft says - the stator inside the convertor could be be at fault.
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thedogsbollox
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Re: Autobox not disengaging.

Post by thedogsbollox » Mon Nov 23, 2009 8:58 pm

Thanks DWH, at least i can give them a clue where to start.
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Re: Autobox not disengaging.

Post by thedogsbollox » Wed Nov 25, 2009 1:49 pm

Ok. This is what is happening. I managed to drive today without having to stop. I drove easily and after about half a mile the box changed up through the gears to lock in even though I was only travelling at about 25 to 30 mph. It struggled to pick up speed as no matter what I did, it wouldn't kick down. I went on like this trying to rev up in order to kick down but it never did it for another couple of miles. It then acted normal.
Any further ideas?
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dandywarhol
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Re: Autobox not disengaging.

Post by dandywarhol » Wed Nov 25, 2009 7:09 pm

Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
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