mk4 gt tdi 130 - Over cooling

[Jay_ConsoleChip]

My car seems to take ages to warm up, even 30 mins constant driving and the needle can be stuck at 70ish, push it a little and it will sit at 90.

So far i have done the following:

Change thermostat + o ring
Change coolant temp sender


Could my fan control switch be gone?

Also i notice if i sit at the lights or idle for a while the temp will start to drop from 90 for example, down to 70.. it does this in the space of around 5-10mins idle.

Anyone have any ideas? im really clueless here, its annoying when it takes so long to get some proper warm air from vents!

Jay

[dazzer]

hello there,try getting ur climate control plug in and have it diagnosed. your climate control controls the fans.cheers

[Jay_ConsoleChip]

the climate control unit controls the radiator fan???

Jay

[dazzer]

try putting ur climate control on econ mode,while running the engine,the fans should be off.put it onto auto,the fans should be on.try keeping the climate control on econ mode and the temparture on 22 c,have the flaps on the window and the feet,try that, after 20 mins the engine should be up to normal working temp,try thatcheers

[STEWY L]

hello there,try getting ur climate control plug in and have it diagnosed. your climate control controls the fans.cheers

hi lads,think you may be talking at crossed purposes here.
jay tends to think radiator fan,dazzer is thinking heater/ac fan.
you may be right jay, but i would have thought that you would have been able to hear the rad fan running.
i could be a million miles away,but no hot water to heater,erratic temp on gauge,would have me thinking water pump impellor?
good luck,
stewy.

[Jay_ConsoleChip]

stewey i think your right there, dazzer thinks im going on about the interior fan, which im not, i just want my "engine temperaure" to be constant and normal.

regarding the fan impellor, surel a damaged impellor would cause the car to over heat?

ive got g12 coolant, new thermostat, and new coolant temp sensor and still the engine stays between 70-80. only hits the middle if its on a long journey and engine constantly kept going. if im at the lights or idle the engine for a few minutes, the temp will start to drop.

apart from the coolant temp sensor which other instruments are used to control the radiator fan? because logically speaking the only thing that can cool an engine is the radiator fan.

Jay

[v6dub]

I had the same problem, i did everything you done, i changed the thermostat, i had the sensors checked, water pump checked, at my local gargage, then my local garage sent it to vw at there expence and they found nothing wrong, so my garage changed the thermostat again at there expence and problem solved, are you sure it is not just your temp gauge on the dash playing up.

[Jay_ConsoleChip]

the gauge is deffo not playing up, as the hot air from the vents isnt as hot when the gauge drops.

[v6dub]

The only thing in your engine that regulates the flow of hot water is the thermostat, maybe the wrong one was put in or it was damaged.

[STEWY L]

The only thing in your engine that regulates the flow of hot water is the thermostat, maybe the wrong one was put in or it was damaged.

i would go along with that. i have never seen one of these thermostats but apparently they are like nothing we "old'ens" have seen before, and i believe
that they have to be fitted "just so" because of some sort of "reaction dowel"
or similar. sounds as if it may be quite easy to get the installation wrong,sending the coolant through the radiator before it has reached opening temperature.
as regards the water pump impellor,if it was damaged,loose or erroded it would prevent normal circulation,with little going to the far reaches of the system,the heater,but yes,you are right,it would usually overheat.