320CDI running temperature

[jeremy156]

I've read a handful of threads that mention engine temperature for the 3222cc inline six diesel in my 2003 E320 CDI. I'm not clear whether I'm looking at a fault with my constantly below 80 degrees, or whether it's perfectly normal considering I drive fairly gently.

I thought a quick poll on the forum might be useful to either settle my mind or nudge me into action.

 

[Dieselman]

It should be 87c. If lower you need a new thermostat, which is pretty common.

 

[jeremy156]

I was suspecting the thermostat, however after my 10 mile journey to work this morning, arriving in the car park with the gauge showing 3 "blocks" below 80 (as is typical on my car - I think that's around 70-ish) I popped the bonnet to feel the radiator and found it to be cool.

Am I right that with the thermostat failing to close (which should delay warming and allow airflow to hold it under the desired temperature) I would find a warm radiator?

 

[Adam230K]

it should be between 80-90, and like dieselman said, if its not, it'll be the thermostat.

 

[Dieselman]

Am I right that with the thermostat failing to close I would find a warm radiator?

Correct. At 70c the rad should be cold.

 

[jeremy156]

Apologies for my ignorance, but with a cold radiator and a low engine temperature, doesn't that indicate that the thermostat is in fact working correctly? Wouldn't a warm radiator at low engine temperature indicate a faulty (stuck open) thermostat?

 

[Dieselman]

The rad can't be warmer than the engine, so a leaky stat causes a warm rad, just as you have.
Check it near the bottom, if warm there you definately have flow.

 

[ceejay]

As Diesalman has said, it sounds very much like you need a new thermostat. I changed mine 3 weeks ago because I had identical symtoms. Engine temperature would eventually get up to about 75-80C after about 10 miles but it frequently ran colder. With a new 'stat it gets to 85C after about 3 miles and then sits steady at around 90C when fully warm - as per the owners handbook.

 

[greggster]

is that an easy change just out of interest?

 

[ceejay]

Very easy, even easier if you are lazy like me and get the guy in the independent garage next to work to do it for you! (Cost me an hour's labour)

 

[ringway]

I had a new thermostat in mine 320cdi.
All round improvements (car runs better/more efficiently) and the heater is now furnace-like, so much so, that you can burn your fingers by touching the blower vents.

 

[renault12ts]

I've read a handful of threads that mention engine temperature for the 3222cc inline six diesel in my 2003 E320 CDI. I'm not clear whether I'm looking at a fault with my constantly below 80 degrees, or whether it's perfectly normal considering I drive fairly gently.

I thought a quick poll on the forum might be useful to either settle my mind or nudge me into action.

3226cc !!! the 648 is 3222cc. Also, to get an acurate reading press "rest" until you change the display. Item 22 ( or is it 6 ) shows temp digitally.

 

[kwakdonut]

3226cc !!! the 648 is 3222cc. Also, to get an acurate reading press "rest" until you change the display. Item 22 ( or is it 6 ) shows temp digitally.

oh Mr Picky!!!

 

[jeremy156]

I just realised.... when I'm feeling for the temperature of the radiator, I think what I'm actually feeling might be the condenser for the aircon... and that the radiator sits behind that, am I right? I'm not sure I can get my hand onto the radiator itself as it's wrapped in plastic with a gap only for the fan - I'll have another poke later and see.

For info, last night it warmed to 60 in the first two miles and only very briefly went above 70, despite some 'spirited' driving uphill to quash the theory that my granddad-driving-style is to blame.

 

[renault12ts]

oh Mr Picky!!!

I know. It's a failing. Sorry.

 

[renault12ts]

I just realised.... when I'm feeling for the temperature of the radiator, I think what I'm actually feeling might be the condenser for the aircon... and that the radiator sits behind that, am I right? I'm not sure I can get my hand onto the radiator itself as it's wrapped in plastic with a gap only for the fan - I'll have another poke later and see.

For info, last night it warmed to 60 in the first two miles and only very briefly went above 70, despite some 'spirited' driving uphill to quash the theory that my granddad-driving-style is to blame.

Mine is like that. On the digital reading I have seen a max of 67, 5 minutes after stopping. I think, like you, the thermostat needs replacing. Funnily, other people with the same p0roblem do not notice an improvemenrt in economy or anything else, but cabin heat is low no slow to come on. Also, the engine may wear more rapidly if running cooler.