Engine Temp in Winter

[Marko]

During these really cold winter nights I've noticed that the temperature barely gets to 90c. When driving casually the temp struggles to get to 70c especially when the heater is pumping air out. Uphills it will start to warm up quicker then going downhill it will begin to cool.

I'm happy that the thermostat and temp sender are all ok as motorway driving the engine gets hot. I'm really surprised how diesels can 'cool off' when not under load, unlike petrol engines. Even idling with the heater on the engine will cool. Does anybody else experience this or is there a problem? I've checked for water circulation and there doesn't appear to be any getting to the radiator, so all seems ok. It has to be cold though, 0c and colder. It's fine at say +5c.

Regards

 

[Kevint]

That sounds wrong to me - I've had both petrol and diesel Audis and they have alway read 90 degrees when warm (unless something is wrong), are you sure the stat is ok?

Kev.

 

[peteA3tdi]

my tdi's doing the same with a new water pump and t/stat (audi parts), it takes over 10 miles to get it up to 90c with the heater set over any thing over 20c if i set it to 18c (still hot) it takes around 5 miles to get to 90c and then if left at idel it back down to 70c

 

[Marko]

PeteTDi - you seem to suffer the same as me. This may be normal, as like I said, it only happens when very cold and not using much acceleration AND the heater is at 20c+ typically 23c. I turned off the heater and it started to climb towards 90c. When I had a faulty thermostat (on my previous pertrol engine) it would cool even in summer.

My personal view, is that this may be normal when the engine is not under sufficient load in such cold conditions. /ubbthreads/images/graemlins/noidea.gif Kevint seem to think it's not and he's had a diesel longer than me. /ubbthreads/images/graemlins/confused.gif

 

[Marko]

PeteTDI - I forgot to ask why you had the new water pump and thermostat?

 

[Kevint]

[ QUOTE ]
Kevint seem to think it's not and he's had a diesel longer than me. /ubbthreads/images/graemlins/confused.gif

[/ QUOTE ]

Mine was a newer version of the Tdi - I owned it for 8 months and 20,000 miles. Always 90 degrees.

Any other opinions?

Kev.

 

[imported_kris_tdi]

i leave my heater on 22 degrees and i can drive for ages and it wont reach ninety on a cold day. efficient radiator /ubbthreads/images/graemlins/smile.gif

 

[Broken Byzan]

Its the heater, i have just changed the stat on my petrol B5, as the temp was around 70 ish instead of the normal 90. And now it heats up much quicker, and is stable at 90, the bottom pipe barley gets warm when the heater is turned up.

I notice that the heater feed and return pipes are placed in the circiut so as when the stat is closed, the rad is basicly bypased. Because we have quite large heater matix's i think they effectivley cool the engine very well

 

[peteA3tdi]

[ QUOTE ]
PeteTDI - I forgot to ask why you had the new water pump and thermostat?

[/ QUOTE ]


when changing the cambelt i found pink marks on/around the water pump, it was dry but must of had a slight leak so just changed it along with the t/stat and coolant

 

[Marko]

[ QUOTE ]
[ QUOTE ]
PeteTDI - I forgot to ask why you had the new water pump and thermostat?

[/ QUOTE ]


when changing the cambelt i found pink marks on/around the water pump, it was dry but must of had a slight leak so just changed it along with the t/stat and coolant

[/ QUOTE ]

I see, cheers. One last question please Pete. What is the recommended mileage for a cambelt change on the 1.9 TDI? Or should I ask what is within a safe margin?

Regards

Mark

 

[arthurfuxake]

1.9TDi cambelt is due at 60k.

 

[peteA3tdi]

audi say 60k
autodata 55k
mine was on 52k , i was doing a oil change and had a quick look to see how the belt was and it was very bad and about to snap
we do a fleet A4's and passats at work and all the belts we have changed have been in a bad way so don't leave it too long

 

[Marko]

Thanks Pete, That does surprise me though! Is it fairly easy on the TDis? I would have had to remove the front bumper on my B5 A4 so took it to Audi. I've only done 21k so I'm sure it should be ok but worth inspection I guess.

 

[peteA3tdi]

yes it's a bumber off job but it's not hard, getting it to line up again is the fun part