HELP! When I start my octavia the radiator cooling fan immediately starts running, even when cold. What is causing this? The coolent level is correct and there are no leaks in the system. Also the water temprature gauge in the instrument cluster works correctly too and registers correct running temp when the enging has warmed up, and doesn't overheat, bringing me to the conclusion that the thermostats are working too and not staying closed to overheat the engine. Is this problem being caused by a faulty sensor somewhere?

Is it a tdi?

No It's 1.6 FSI (BLF) engine code. I think VW designate it (BAG)

Mk 2 octavia

I'm guessing it's the

Coolant temperature sender

G62

looked @ wiring diagram for car

Hi ,

1.9 d Octavia elegance .

My radiator fan never ever came on until I changed the a/c condenser and recharged the a/c system, Now its seems its always on whether or not the a/c is switched on or not. I also changed the pressure switch for the a/c. Its mostly noticable when switching off the engine and the fans then stop. They dont run on.

It may be your a/c system fan if you have one.

Edited 30 December, 201213 yr by erindad

It's defo the cooling fan because i'm now gettin strange readings on the temp gauge. And if i switch on the a/c the other fan starts which i presume is the a/c fan

After originally posting this problem, the problem seemed to solve it's self. But now it has reared it's ugly head again, So any help is much apreciated

The symptoms are:

When the engine is started the righthand fan (as viewed from the frount of the car) comes on (engine temp cold or hot)

The fan runs for a minute or two, then stops

Then starts again, with this cycle continuining

 

I now have a hand held diagnostic tester so i will plug it in this evening and post the results tomorrow

(also the car is petrol so it's not a dpf cleaning cycle)

Thanks

Again this problem has stopped again, but i have used my tester anyway and 3 codes appeared.

Right here we go, 3 fault codes:

 

16575

Fuel pressure sensor

G247: Implausiable signal: P0191

--------------------------------------------

Sporodic 004-No

 

 

16500

Engine coolent Temp sensor

G62: Implausiable signal: P0116

 

18369

Exhaust Gas Temp

sensor 2 Bank 2

G449: Electrical Maulfunction: P1961

 

Could any of these fault codes be causing the fan problem? I'll check these codes on the ross tech website.

I also notice the same coolent temp sensor has been flaged up as I was suspecting before, looks like this could be a probable cause?

Also could i First erase these fault codes and see if they reappear?

Any help, Thanks

sounds like you need a new coolent temp sensor, I had to replace one of these on my 1.8T Cupra and it was a doddle

Looks like thats the road i'm going to go down, Mabey check wires for damp or damage first. I'll see if i can get a sensor at my local spares shop

Right finally got round to changing the coolent temp sensor, because problem has returned, but....

It hasn't solved the problem..

So pluged in diagnostic tester and the temp sensor code has changed from above, to:

 

16502: Engine coolent temp sensor (G62):

Signal too High: P0118

------------------------------------------------

Sparodic 002-lower

 

 

Does this mean the new sensor is also kaput, or is there some other problem in the system?

Thinking mabey, Coolant Fan Control Module/Relay?

Is it possiable?

One more thing there is a slight leak on the radiator, but I can't see this having a bearing on the situation though. (I keep the coolent at the correct level)

Is the car smokey at all?

You have mentioned keeping it topped up. But have you flushed the system. Try the simple things first that are less cost effective. Good flush might solve it.

In reply to smoke, No blue or black smoke, but it can be a little smokey with white smoke on start up. But if your thinking head gasket it's fine in that department, no oil in water/water in oil.

Regards to flushing system, it probabley has never been done, but it does look pretty clean. Also reluctant to change it, because if It has to go to Skoda dealership they will have to drain it anyway, and it seems a bit of a waste. (even if it's only a tenner).

 

P.S. The car is actually back in hands of my father, I drove it for about year and half, but insurance was exorbitant, so went back down the felicia root.

It's just I had a similar problem on my petrol and I replaced the water pump. You have already mentioned that your car doesn't overheat so it beats me to what if could be. My car was letting off a lot of white thick foggy smoke but was not fuelling or oily fumes if you know what I mean. Don't know how to explain it really apart from that.

Best of luck with it buddy and keep post updated when it's resolved. I will follow the thread.

Gizmo.

Funny you should mention water pump, because my father suggested that, but we were just guessing.

Think it will have to go to skoda,  I hate to think what it will cost though. 

Thanks anyway, I'll post future developments when they come.

Hopefull to finish up this thread, and to help any one with similer problems:

Looks like replacing the coolent temp sensor did do the trick. (because it was a intimitant fault I can't be 100% sure it's cured, but lets hope)

The problem with the sensor was my fault, me being new to using diagnostic equiptment, and the manual giving lots of warnings about erasing fault codes, I had decided not to.

But it seems that the fault code needed erasing after changing the sensor. So thats what I did yesterday and there has been no problems since (cars been to sheffield and back today)

I'll check for codes in about a weeks time

And I'll ask my father weither he wants the coolent changing as well.

 

P.S The sensor was a cheap one from ebay (grey with 2 pins), cost £5. Hopefully it will last

Glad to hear it's resolved.

My octavia has had engine temp sensor changed 3 times but the same code keeps appearing no idea what it could be ??? Please help.

The only time I've ever noticed the fan come on with my MK2 1.6 MPI is when i'm using the air con.... Never noticed it any other time, even when sitting idle in traffic for ages! The temps gauge stays at 90 when the engine is warm and I've never seen it go any higher. 

my old Octavia had two temp sensors , one in the radiator pipe and one in the c/head/thermostat area. both were the same two wire type and not the 4 wire type

I changed both of them but still having p0118 mil on and fan on constantly please help ????

Did you erase the fault code after replacing the sensors? Like I posted earler, this problem didn't go away untill I did that.

I will also point out that the cheap sensors ARE useless, the replacement sensor I used was knacked again after 6 months.

yes i cleared fault code but it keep reappearing within straight away also my car runs sluggishly, no idea what to do i have used original VW Sensors.still no luck