W203 C200 CDI LOW Temp issue

[EricManchester]

Hi guys, I recently noticed a LOW temp issue with my W203 C200 CDI (with DPF) coupe.

After engine starts, the temp gauge slowly rises to about 80'C (never exceed it) but only keeps there for a few minutes and then drops to around 60'C. The temp may rise again to 80'C in traffic or with some harder accelerations, but always drop to 60'C and keep it there; even when driving on Motorway with consistent speed; say 70 MPH.

I had read some threads and most of people found it was due to the bad thermostat. The thermostat is cheap enough to buy but my local garage quoted me £100 for labour. However they also advised me to do the diagnosis first to make sure it is the thermostat problem. The diagnosis will cost a further £40.

I am just wondering that if it definitely sounds like a thermostat issue so I should change it w/o the diagnosis?

Also some threads mentioned that it will be only 1/2hr work to change the thermostat, could you recommend any good garage to do the replacement in/near Manchester? Many thanks in advance.

 

[Chrishazle]

Sounds very similar to my S203 C270 not long after I got it. Is your heater useless? Thermostat sounds a good call to me, sod the diagnosis -and the garage that wants to charge you £100 (no doubt +VAT!). I bought the thermostat myself, and my local garage fitted it for £40 (admittedly 3-4 years ago), or there's a good "How To" on here or t'other side, it's apparently not difficult to DIY.

 

[Dieselman]

It is the thermostat, it's a common issue.

Fit it yourself in 30 minutes, including topping up the coolant.

 

[Chrishazle]

There's good info in the "How To" when you find it - things like IIRC removing the oil filter to make access easier, being very careful of the plastic fuel pipe close by, dropping the coolant level by an amount beforehand (and keeping the fluid so you can put it back afterwards!). IIRC the "How To" is about either a C220 or C270, but notes straight away that others are the same. Can't remember the poster on here, but IIRC on t'other side it was Helpthisdude.

 

[Dave Richardson]

I had a similar problem a year or so back, a new thermostat solved the problem, in about 45 minutes & that job was completed on the driveway not a work shop.

Follow Dieselman's advice

 

[jaymanek]

Use an MB thermostat as they come with a new temp sender installed... the old one can get stuck in.

 

[rf065]

Use an MB thermostat as they come with a new temp sender installed... the old one can get stuck in.

And the MB one is the same price or cheaper than aftermarket versions too.
Only £36 for mine.

Russ

 

[EricManchester]

Sounds very similar to my S203 C270 not long after I got it. Is your heater useless? Thermostat sounds a good call to me, sod the diagnosis -and the garage that wants to charge you £100 (no doubt +VAT!). I bought the thermostat myself, and my local garage fitted it for £40 (admittedly 3-4 years ago), or there's a good "How To" on here or t'other side, it's apparently not difficult to DIY.

Thanks for your reply.

The heater works fine once the temp rises to above 60'C. In this case do you think it is the thermostat problem?

 

[EricManchester]

There's good info in the "How To" when you find it - things like IIRC removing the oil filter to make access easier, being very careful of the plastic fuel pipe close by, dropping the coolant level by an amount beforehand (and keeping the fluid so you can put it back afterwards!). IIRC the "How To" is about either a C220 or C270, but notes straight away that others are the same. Can't remember the poster on here, but IIRC on t'other side it was Helpthisdude.

Many thanks! I will do it by this weekend.

 

[EricManchester]

Thermostat changed.

Temp now stays above 80'C all the time after warming up.

Many thanks for all your helps.