w124 auto box question

[e36bob]

My wife runs an E36 amg estate.
The car has full service history.
From a cold start, the auto box stays in second gear longer than when warm. Once she has dropped into third and then fourth, second gear changes correctly again. When we bought the car at 155,000 miles it was just noticable, but now at 170,000 the engine holds 3000 revs in second for roughly ten seconds and then changes.
The auto box transmission fluid and filter were changed at the recent service
and apart from this quirk, the auto box is excellent and changes are very smooth.
I seem to remember a thread on this subject but couldnt find it.
The thread seemed to suggest that this is normal to allow the cat to warm up quickly.
Can anyone shed some light on this please.
My w124 230 te estate auto box doesnt do this, and the car has a cat also.

Thanks in advance for all replies.
W124 estates : apart from the fuel consumption, fantastic cars.

 

[Keith]

fuel consumption

My wife runs an E36 amg estate.
W124 estates : apart from the fuel consumption, fantastic cars.

sorry cant help with the problem on the auto box change up but if you want better fuel consumption try an E300D , 33mpg, smoother at speeed and more pull than a 4 pot petrol model .

Keith

 

[turnipsock]

Check the vacuum pipes

 

[andy_k]

the gearboxes are designed to change differently when cold - as you say to warm everything up quickly.

It should happen on the 230 as well but it will be less noticeable - are you sure that has a cat as most 230's were "pre facelift" ?

As for fuel economy, a well serviced 230TE will easily do 35mpg on the motorway and 30 mpg around town (well ours does anyway). For a 2.3 litre, 7 seater car that seems pretty good to me

Andy

 

[kth286]

e36bob

It is perfectly normal and is described in the handbook (if you have one).

Yes - it is to ensure 'cat' gets hot in shortest possible time and therefore limit emissions.

Regards

 

[e36bob]

Thanks to all for the replies.
I did glance through the handbook , perhaps too quickly.
Why the auto box spends longer in second gear from cold has increased over the time we have had the car is interesting, perhaps there is a temperature sensor somewhere.
Regards,
Bob

 

[Tomkinsm]

My 300CE-24 also stays in 2nd for about 10 seconds (roughly 100metres?) when cold. I just drive it slowly, keeping the revs down for these first few seconds before it changes up. I guessed it was just normal for a cold start.

 

[turnipsock]

are you sure it's not just the oil in the gearbox that is cold and it behaves differently.

I was always told reving a cold engine is a really bad thing.

 

[benzfanatik]

High Revs

Hello, I was having this same problem (only to find it wasn't a problem) When the engine is cold (before it hits 40 degrees centigrade) the car won't shift. I called my local Benz dealer and they said it was perfectly normal for this to happen. I have 2 E320's and it does it on both of them. Watch your temp gauge, and as soon as it hits the second mark, it will shift. As for it lasting longer, you probably jsut need a new thermostat. Good luck!

 

[42731]

300CE-24v

My car does the same: if you keep to low revs for about 20 seconds or so, it will change to third and fourth readily

 

[turnipsock]

When I had my gearbox rebuilt, I found that it wouldn't shift when cold. For a while I had to get to about 50 mph to get it to go to 4th ( not ideal in 30mph zone)

I eventually found that one of the vacuum pipes wasn't seated properly. The vacuum does get worse with time as things wear out.

 

[pascal]

Yea, Turnip,

And it wasn't you who left it off (seriously). Sometimes its best to do these bits of work yourself. When its yor own car, you are more careful with all the little bits and pieces, and don't take any chances.