Disabling the upshift delay on W124

[5907]

Not a fault; I know that it's designed to warm up the cat, both of my W124s did it.

I, However, find it tiresome. When I set off from cold people must think I'm a learner that doesn't know how to change gear. I have to rev the hell out of it to get it to change into 3rd when cold, usually to over 6000rpm. Very embarrassing.

After the frist two changes or so it changes normally.

I'm guessing there's some kind of electric valve somewhere; maybe one of the contacts could be earthed / disconnected to disable it?

Anyone familiar with the 722.4 gearbox?

Thanks.

 

[television]

For a start this box does not warm up the CAT, so something else.

The listed fault is the K1 spring

I can send you the details

 

[ALFIEBEARD]

Not a fault; I know that it's designed to warm up the cat, both of my W124s did it.

I, However, find it tiresome. When I set off from cold people must think I'm a learner that doesn't know how to change gear. I have to rev the hell out of it to get it to change into 3rd when cold, usually to over 6000rpm. Very embarrassing.

After the frist two changes or so it changes normally.

I'm guessing there's some kind of electric valve somewhere; maybe one of the contacts could be earthed / disconnected to disable it?

Anyone familiar with the 722.4 gearbox?

Thanks.

Hi I am not sure about the 722.4 Gearbox, but I had exactly the same problem when cold and apparently there is no way round it, BUT I have just started a thread about the 722.6 box and you could try this procedure, it really helped mine.
Regards
Alfie B

 

[5907]

For a start this box does not warm up the CAT, so something else.

Thanks for the reply Malcolm, but I think it does. It says so in my User manual, Page 72:

"Shifting after a Cold Start
Vehicles with catalytic converter

The upshift from 2nd to 3rd gear is delayed, occuring at a higher engine speed than when the engine is at operating temperature

This means the catalytic converter starts reducing the amount of pollutants sooner."

It is completely normal W124 behaviour and is well known to most, so there is no fault.

I'd just like to know where the valve is to disable it, since the 14 year old cat probably isn't working properly anyway and it's just a bit annoying.

 

[5907]

BUT I have just started a thread about the 722.6 box and you could try this procedure, it really helped mine.
Regards
Alfie B

My 722.4 is hydraulic and controlled with electric valves, and as such can't be reset like the computer-controlled 722.6

 

[television]

Thanks for the reply Malcolm, but I think it does. It says so in my User manual, Page 72:

"Shifting after a Cold Start
Vehicles with catalytic converter

The upshift from 2nd to 3rd gear is delayed, occuring at a higher engine speed than when the engine is at operating temperature

This means the catalytic converter starts reducing the amount of pollutants sooner."

It is completely normal W124 behaviour and is well known to most, so there is no fault.

I'd just like to know where the valve is to disable it, since the 14 year old cat probably isn't working properly anyway and it's just a bit annoying.

Sorry if I was wrong on that point, never the less the over long up shift is covered in the paper I can send you, there is nothing else listed

 

[ALFIEBEARD]

My 722.4 is hydraulic and controlled with electric valves, and as such can't be reset like the computer-controlled 722.6

Hi oops in that case dont try my procedure chuckle chuckle.
Alfie B

 

[5907]

I take it nobody here knows how the upshift delay system works?

 

[television]

I take it nobody here knows how the upshift delay system works?

It has to be a temp sensor thing, the engine ECU is linked to the gearbox ECU so the info goes down that line

The spring that I spoke of does affect 2-3 changes

 

[5907]

It has to be a temp sensor thing, the engine ECU is linked to the gearbox ECU so the info goes down that line

The spring that I spoke of does affect 2-3 changes

As I said earlier, it isn't a fault because it goes back to normal after the first two changes or so, I'd just like to know where the valve is that controls the delay.

 

[television]

Without being a gearbox specialist its hard to answer.

Thinking back, the vacuum system also controls the shifts and the pipes should be checked the modulating vacuum valve is involved here

http://www.detali.ru/cat/oem_mb2.as...GA=722.607&CT=F&cat=45Y&SID=82&SGR=345&SGN=18