Ahhh, now i really found the kickdown switch- whoooosh roooaaarrr!

[se97mlm]

hehe i finally found the "real" kickdown switch in my c240 tonight! thought i had got it before, but obviously not. That's damned addictive!!!

Thing is with such a large pedal that is quite heavy it takes a good old shove! seems the smallest backing off reverts to the next gear, which must have been what i was doing before!

Is it normal for the five speed autobox to be a little whiney in 1st-3rd? It sounds really fantastic in 4th over 4k rpm... Maybe a gearbox oil change will cure the whine?

Thought of a good fuel saving mod if we can find a good chiptuner, which would be to remove that "change up late when it's cold to warm up the cat" feature; cold starts are really thirsty

 

[C240Sport97]

gearbox oil change makes a real difference, especially if your car has done about 60k miles. what others say:

http://mbclub.co.uk/forums/showthread.php?t=8973

 

[portzy]

Thought of a good fuel saving mod if we can find a good chiptuner, which would be to remove that "change up late when it's cold to warm up the cat" feature; cold starts are really thirsty

The dealer will disable this feature if you ask them but, they add the warning that 'if the cat fails sir it will not 'nessesasrily ' be covered under warran....' you know what I mean

Regards, Portzy.

 

[Steve_Perry]

Hehe, nice one Enjoy

As mentioned above the 'cold engine' gearbox remap can be programmed out but to be honest with you, if you go for a gearbox oil change you will find the gearbox's cold engine performance vastly improved and should be much smoother on changes even if the revs are kept high to warm the cat up quickly.

Gotta love that Kickdown 70mph is my fave: tootling along... hit the warpdrive and the car drops to 3rd and redlines its way to higher speeds. *Ahem* not that I do that sort of thing you understand it's what I've read elsewhere

S.

 

[RichardM]

If you have the tiptronic box then when your driving with the engine cold, if its holding the revs push the gear lever over to the + (even though it is already in D), this will force it to change gear.

 

[PJH]

*Ahem* not that I do that sort of thing you understand it's what I've read elsewhere

S.

I read it in another thread too, but it was the same author !!

 

[fuzzer]

If you've have the tiptronic box then when your driving with the engine cold, if its holding the revs push the gear lever over to the + (even though it is already in D), this will force it to change gear.

It does , i use it all the time. :bannana:

 

[jimmy]

Remember it is good for the engine to warm it up quickly not just the CAT. An engine has an optimum operating temperature where it will be most effiicient.

 

[Robbo]

If you've have the tiptronic box then when your driving with the engine cold, if its holding the revs push the gear lever over to the + (even though it is already in D), this will force it to change gear.

You learn something new every day!

 

[se97mlm]

but Jimmy, you will warm an engine up much more quickly by demanding a high torque at low revs, than revving highly with little load or trailing throttle. Not to mention the wear caused because the oil has not had chance to circulate properly.

Similarly this is why it is a complete disaster to warm your car up on a cold day by idling it while you go in and have a cuppa. We did an experiment in Stuttgart with a 2.2cdi engine, starting from ambient temp, and idling for half an hour. The water temperature rose to operating temp, but the oil was still only 2° above ambient! as soon as we gave 50Nm resistance on the dyno, the oil temperature climbed like a rocket; it was at 70° within a minute.

Moral: on a cold day ALWAYS drive off straight away. The water temp gauge does not tell the whole story regarding lubricant temperature, and thus the wear you are causing to your engine.

The warm up the cat feature is almost certainly for the benefit of emissions testing, as the euro regulations stipulate testing from a cold motor. In reality, this costs the end user every time he/she makes a cold start. Car manufacturers have to win sales by selling cars with low emissions to get low tax for company drivers here and all drivers in Germany. Bit of a bugger for private motorists, but that's life.

Emissions are a very political thing. Think of all the jets dumping millions of tonnes of exhaust gases into the atmosphere so high up, yet our government thinks this is less important than improving the economy of our vehicles; improved emissions are always a trade-off against exhaust emissions, hence why economy has not improved so drastically as it has had the potential to do over the last years. In tandem with this, governments well know of course how much duty they would lose if cars were to use 50% less fuel.....

Don't know if it's an urban myth or not, but i have a colleague who worked at a British car company in the early nineties. They had a family car capable of 80mpg then but were leaned on very strongly by the government, who suggested that financial assistance would be a lot harder to come by if this vehicle were to go into production... makes you think. Project was mysteriously cancelled.

 

[RichardM]

It does , i use it all the time. :bannana:

Sorry, I should have added as told to me by Fuzzer!