New guy here, just picked up a new (to me) C204 250CDI

[JD427]

Hi all, just joined after having picked up a 2013 C Class Coupe yesterday so thought I'd say hi and ask a few questions!

So, in no particular order:

1) The temperate gauge: once up to temperate it seems to sit above the middle of the gauge, 80 degrees being middle, and mine goes to 85 and sometimes 90, seems to fluctuate between the 2. Is this normal? I've come from an Audi A3, where the needle would sit slap bang in the middle of the gauge (90 degrees) and never budge!
2)Idle: very very slightly bouncy RPMs at idle, engine seems fine and doesn't appear to be any 'misfires', the needle will move around 1mm or so, very small but enough for it to be observable. Doesn't matter if the engine is hot or cold, always does it when idling. Again is this normal?
3)Sometimes a graphic will display on the dash indicating the rear passengers don't have their seat belts on, I'd ask them to put it on, but the thing is, there aren't any there! Would this be a sensor issue?
4) Sometimes when putting the car into reverse, I'll hear some kind of motor running, kind of like the sound of the window being opened/closed. What is this?!
5) Finally, how does the 250CDI respond to a remap? Is the 250 the same as the 220 but with a slightly different remap done already - therefore not giving much room for improvement?

Thanks all, sorry for the all the questions, I'm new to MB, I've never had one and been sat in an Audi for the last 6 years!

Cheers

 

[Gazwould]

The thermostat is more accurate than VAG but a weak point and may want changing , integral CTS I believe .

VAG 'stats can sit at 90 but could actually be somewhere from 70 - 110.

The 250 have probably larger injectors or something limiting the fuel delivery on a 220 , but 250 definitely has a larger 2nd turbo .

Water pump and fuel filter coolant inlet outlet housing will spring leaks at some point as the parts have been redesigned .

Oh and switch off stop start if it's operational .

 

[OneForTheRoad]

Ecp states the stat opens at 95. Which seems to take an age to happen even in my 15 plate 250.

 

[JD427]

The thermostat is more accurate than VAG but a weak point and may want changing , integral CTS I believe .

VAG 'stats can sit at 90 but could actually be somewhere from 70 - 110.

The 250 have probably larger injectors or something limiting the fuel delivery on a 220 , but 250 definitely has a larger 2nd turbo .

Water pump and fuel filter coolant inlet outlet housing will spring leaks at some point as the parts have been redesigned .

Oh and switch off stop start if it's operational .

Haha yeah, that's another thing, can't stand the stop start, I'm having to turn it off each time I start the car. I don't believe there's an easy way to switch it off permanently is there?

 

[Gazwould]

An obd port thing , a removal of something on negative battery terminal but also gets rid of the handy 'hold' function or it does itself when battery voltage is low 12V but still starts perfectly .

More the mystery is the gearbox mapping top rpm upchange point and kickdown switch activation that causes the dropping of two gears..

 

[markjay]

The W204 has rear seat belt sensors, but it does not have weight sensors in the rear seats, so the car knows if the seat belts are buckled or not, but it does not know if anyone is a actually seating there.

When you drive-off with no occupants in the rear, or with at least one unbuckled seat belt, the graphics will come-up as a reminder. It will go away if you press the OK button on the left side of the steering wheel, or it will go away by itself after 30 seconds if you take no action.

The graphics will also come-up if a rear seat passenger unbuckles the seat belt while the car is in motion.

 

[markjay]

There is no 'easy' way to permanently disable the Stop/Start function.

There are some unofficial ways... as per the post above.

I just switch it off at the start of every journey.

 

[JD427]

The W204 has rear seat belt sensors, but it does not have weight sensors in the rear seats, so the car knows if the seat belts are buckled or not, but it does not know if anyone is a actually seating there.

When you drive-off with no occupants in the rear, or with at least one unbuckled seat belt, the graphics will come-up as a reminder. It will go away if you press the OK button on the left side of the steering wheel, or it will go away by itself after 30 seconds if you take no action.

The graphics will also come-up if a rear seat passenger unbuckles the seat belt while the car is in motion.

Ahh cheers! Yeah it does go off after a bit, bit weird really! You'd think it would only show if someone was sat there without their belt on!

 

[Deletedmember130310]

Re temp gauge
Both your MB and Audi show 90 degrees- what’s the problem?

 

[JD427]

Re temp gauge
Both your MB and Audi show 90 degrees- what’s the problem?

Because it goes between 85 and 90, it doesn't stay fixed in one place, it doesn't stay fixed in the centre of the gauge. I'm not saying there is a problem, I'm just seeing if it's normal.

 

[Smart320]

Never had one of your model, but had E class / ML /A / and now an SLK and in all of them the temperature was steady once up to temperature, even in slow or standing traffic . Am sure other members with technical knowledge will comment further

 

[Atavus]

I think some manufacturers have ‘damped’ the temperature gauge, just to avoid such queries. Interrogation of the ODBC port can reveal a difference.