Motor temperature Edition 30

[plex]

Hello everyone,

I see now a curious phenomenon on my Gti.
Let me explain, but hopefully, the engine breaks down quite often. Once the optimal water temperature is reached, if I drive the temperature is correct, around 80 - 82c °, Climatronic data.

The engine has always ventilated regularly but right now, it's stronger.

If I stop, the engine temperature rises gradually up to 2 minutes 87 - 88c ° and the fan goes off, quite noisy, as some have noted, to drop the temperature to 81 - 82c °. Then after 2 minutes, again. The breakdown occurs even if the climatronic is off.

Today it was about 25c degrees outside and I got a few ventilation after 2 minutes at rest. However, I have noticed during my research on the difference between 30 and Gti Edition classic, the calorstat not manage the same way: 87 ° C thermostat INSTEAD OF 80 ° C.

The oil level and the LDR are quite correct, I have no default vagcom or on the dashboard.

By the way:
- The car works very well
- The coolant is at the right level
- No mayo in the jar
- I never saw temperatures exceed 90C ° to the ODB or on the Climatronic.

Maybe I can:
- Change the sensor? I think there must be more than one right?
- Do a purge of my LDR?

My tracks at the moment:

However, I must do the oil change, oil (long life) with only 15 000kms. This can probably already reduce this phenomenon? A new oil for better lubrication?

Also note that I installed a Catback non resonated? Some say it is wrong not to have the entire line.

Perhaps the calorstat is HS?

Maybe it is normal?

In advance, thank you

 

[Richn83]

There are indeed two sensors one at water out of engine block (displayed in cluster, and figure you see at OBD2 at 80-90 degrees) and a radiator out sensor which will generally show temps down at the 30-50 degree level.

As for temps of coolant I see a pretty much constant level of temp at the coolant exit to engine sensor that only fluctuates 2-3 degrees (I have stnadard GTI K03) and it is always around 87-91 range once warm.

I have Polar FIS system fitted in my car so I can monitor all the temps in my high-line screen so I watch the coolant temps and oil temps constantly.

If you coolant fan is very noisey then that would suggest to me that maybe your larger fan is constantly cutting in, this occurs when the small fan breaks normally due to a faulty rheostat so it would be worth checking if the small fan works (it will be constantly on with A/C due to the need for flow of air across the A/C radiator/condenser.

https://picasaweb.google.com/lh/photo/WTs_l7CLHS7VLzdtjHKm5DIbjg7Zt11gF9VrQzaU1sQ?feat=directlink

[plex]

Thanks so much Richn83.

I will start the engine and check if fans works  

I have some noise if A/C is on yes, and I have the same noise if coolant goes to 88c° (climatronic)
Maybe the larger fan is always cutting in ... ...




Thanks  

[Richn83]

Sounds like your small fan is caput then, think its a fairly common fault it isnt the fan itself so to speak I believe it is the controller, and if the small fan doesnt work then it will need to use the larger fan.  I would guess this would also explain the strange coolant temps you see as I would imagine the larger fan which is the final cooling option has a larger hypothesis (it is run longer than it takes to reach optimal temp down to a lower temp to shorten the amount of time the fan needs to run) than the smaller fan as it is slightly more intrusive.  Hope its that simple 

[plex]

Thank you very very very very very much  Richn83.
I do not understand exactly what you said because of my bad english level but I think I understand :)

Please confirm :

When I start the engine, coolant is cold, like 20c°.
After few miles or km, engine coolant is at 80c°.
If the car run, fans don't have to work because of running ^^
If the car do not run, coolant goes to 88c° and then the fan start.
Small fan need to work more time and stronger to have a lower temp than the bigger one.


So :
First, I have to control which fan start at 88c° A/C off.
I will see if the biggest fan work or not.
If biggest fan do not work, it can be the controller, the relay or maybe the fan himself.

Thanks sooo much for all your help.
I will check as soon as possible :)

[Richn83]

exactly if you are moving and the car see's a big enough temp drop across the radiator then the fans will stay off, if you are not moving (in traffic) with engine running and the temp difference across the radiator drops the car will start the electric fan to cool the coolant.

As standard the small fan will be used first to maintain the working temp of the coolant, if this is not sufficient air flow and temps continue to rise then they will switch on the larger fan to provide an even larger air-flow.  However if the small fan does not work then the car will switch the large fan when it would normally be sufficient to just use the small fan, this is normally noticed as the large fan is much noisier and can provide slight vibration.

It is also normal for the small fan to be constantly operating when the aircon is switched on as the A/C radiator needs air-flow to work, so a simple test of your radiators is to switch ac on and see which fan spins up, if its the large one (especially if car is cold) then you should know that the small fan is faulty.

[plex]

Yeah, my english level is not so bad :)

I have some vibrations when the fan starts ... so I guess vibrations comes from the big fan.
It goes in the same direction of your hypothesis small fan faulty.

I will check the small fan & beat him up ^^

Awesome Thanks Richn83 !

[af1]

I had to laugh at no mayo in the jar... sorry

[plex]

 

[plex]

Hello everyone,

I'm here to give us some ... bad news :(

Today, I'm testing ...

1. If the car do not run, coolant goes to 88c° and then the big fan start (noise)
2. If the car run with A/C on, I have the same noise for 1st step
3. If the car do not run, coolant is at 80c°, no fan works :(

So I tried to run big FAN with my hand, coasting it works.
I tested on the small fan, and it runs only with great difficulty.
It seems Richn83 have found the solution >> The small FAN does not work.
RIP small fan

I think that replacement operation will be hard ? I have to remove front bumper and I/C ...
Is there any other solution please ?

[plex]

Hello all here.

Here's good news of my rabbit gti.
This Sunday, I did the oil service.

I then saw that it was possible to disassemble the entire block of ventilation.
This one is indeed fixed with four screws.

My little FAN was seized, I put some penetrating oil (WD40) and it works again.

A big thank you for your detailed help!

friendly

Plex

Richn83 

[Richn83]

Glad to hear all is well again Plex, I wonder how many more small fans are just seized and not fully broken that could save some people a lot fo money as the fan units are not cheap 

[plex]

You're absolutely right.
I will check this regularly.
I also informed the members of my forum French need to be careful and one member appears to have the same worries.
Thank you again for you 

[Top Cat]

Thread of win.  

Plex you have amazingly good, bad English.