strange cooling issue !!!!!

[tony gee]

I thought I'd do a separate thread in this section.

so i picked up a 2012 C204 coupe yesterday with the 1.6 M274 engine. on the way up the M6 i noticed the temp gauge slowly rising till it went into the red !!! so pulled over and within a few seconds of stopping the gauge started to drop, so back on the motorway and was fine for a few miles and then did it again, this time into a service station and let it cool down so i could check the fluid level, that was fine so back on the road and ok for about 10 miles or so and then it started to rise again !!! but for some reason i turned off the heater ( didn't have A/C on) and within 3-4 seconds it dropped back to normal ??? later on i put the heater back on and same thing it started to rise. turned of and dropped straight away so left the heater off.
got on the slower A roads and put the heater back on and it was perfect the 35 miles to my house, you can drive it all day long at none motorway speeds and its perfect, it seems to only do it at 70ish MPH but not at 50 MPH or less !!!!! very strange ???
I plugged my scanner in and found a P02170 code ( coolant sensor) so I'll get that changed and also the thermostat housing done under warranty.
just can't understand why it does it at speed with more air flow and the heater on ? back in the old days that would keep an engine cooler !!!!

 

[tony gee]

bit of an update, spoke to the seller (garage) and they said get it booked in to my local garage and get them to sort it, and what ever it cost the seller will pay for it all. they are very helpful, makes a pleasant change

 

[AMGeed]

^ Sounds like a decent trader if he comes through with payment.
We are quick to condemn poor service, but good customer service is often taken for granted.

 

[tony gee]

^ Sounds like a decent trader if he comes through with payment.
We are quick to condemn poor service, but good customer service is often taken for granted.

yeah i was really happy with how me n the Mrs where treat, the boss wasn't their but when i foned up today i spoke to the main man, and will fix any issues it has. theirs a few !!!!!! I was seriously thinking about getting my c200 back as that had no problems at all and its 5 years older !!!! but i know the C204 will be sorted now, plus I love it.
just look at it