Gear Box Woes

[Benzowner]

Mt S320 petrol is experiencing gearbox problems. When driving normally the gear box works as it should. However, when I kick down, the gearbox goes to a lower gear but will not change back up unless I take my foot off the throttle, and if I boot it hard, the gearchange is very bad, like a gap between selecting gears which results in the higher gear being snatched and the car lurching forward. I have tried the gearbox reprogram with the key on/off etc. but no change. It is a 5 speed auto. Any suggestions before I book the car in.

 

[television]

When was the fluid last changed and the filter

 

[Dieselman]

Possible MAS problem.

 

[Benzowner]

When was the fluid last changed and the filter

The car is a 1999 and only done 45k miles, I would not have thought the fluid would be the problem

Possible MAS problem.

I thought the MAS was on the air intake of the engine, or am I thinking the wrong thing, I probably am

 

[Dieselman]

It is but can create shift irregularities as it tells the ECU how much air is being injested, thus the power output of the engine.

 

[BlackC55]

They maybe a fault in the memories.

First thing is to check the atf level.

 

[karlefr]

Hi
try resetting the gearbox!

As far as I remember:

Switch ignition key to "2"
20 seconds kickdown
Switch ignition key to 0
Leave key inside for 2minutes

That should reset the gearbox to it's original state!

 

[karlefr]

Sorry, I just read you did it already!

 

[television]

If the power output from the engine is not correct, then the gearbox will not respond correctly.

As dieselman says try the MAF, this has cured many of these faults, you could unplug it it and try the car.