Thread: Automatic wont do Drive

urmmmm

which vehicle with what auto...

with just those symptoms youd be looking at a lot of things as potential causes.

what happens if you actually shift it back to 3 or hit the sports/manual gear shift selection?

Originally Posted by chev28

Travelling along the highway today and all was well with the world passing me by at 110km/h in my 1998 300tdi Discovery.

Then the auto shifted itself mysteriously from D into 3 and brought the whole show back to 90. The stick was still on D but it was doing 3. Any attempt to get past 90 made it kick down further to 2 and if I slowed below 60, it downshifted to 2.

So I stopped for a look and ther was no problem with the auto fluid (had it serviced 6 moths age). Engine was fine and idled and revved just fine. So I limped home at 80-90.

Yesterday, I drove some fire trails. Some pretty steep downhills in 2 Low and generally pretty dusty but nothing extreme.

The only thing that did bother me under the bonnet is that my auto dipstick has a habit of popping up about 20mm and it was probably up when I was going along the dusty fire trails.

Any ideas? Could dust have travelled down the dipstick and clogged something?

dave open your eyes....look at the red text

I've tried shifting into 3 and then back to D and it makes no difference. I also tried N then D and it went back to 3.

I've also tried 1-2-3-D from a standstill and it wont go to D.

It really has me stuffed why it kicks down to 2 when you push it above 95 and why it downshifts to 2 when it goes below 60.

check the throttle position calbe (the one that goes from the throttle linkage down to the auto for freedom of movement and adustment...

thats a pretty extreme version of excesive tension on the cable but it sort of fits. its the first and cheapest thing I can think of

Originally Posted by Blknight.aus

check the throttle position cable (the one that goes from the throttle linkage down to the auto for freedom of movement and adustment...

thats a pretty extreme version of excesive tension on the cable but it sort of fits. its the first and cheapest thing I can think of

Spot on Dave, I wouldnt think it would be anything else.

The tell tale sign is that it wouldnt go over 90kmh in 3rd, mine happilly pulls to 110 in 3rd, probably more and my throttle cable is set below full throttle for obvious reasons.

I can think of at least 3 other things that have the potential to cause this in conjucntion with each other and generally would fail in a daisy chain sequence...

but if these things were to head that way then the life of the box is going to be very very short

to prepare you for the worst..

failure of the G2 pressure line or the vanes that provide the pressure (which implies at least some damage to the final planetry setup as the vanes hang off of that)

seizure of the final clutch so it cant do its job and let it shift up to the last gear

pressure regulator failure thats making the box think that you have more throttle on than you do as its allowing more pressure to be generated

selector valve failure for the last gear

line blockage...

The cable has plenty of slack.

Which of the other possibilities would cause the downshift to 2nd when the car goes below 60?

Thanks for the quick replies by the way.

Ray from Canberra Motor Works took off the pan and found burnt bits as well as some sort of square flange piece.

Out with the old and in with the new.......

You just never seem to get ahead these days.