Punto (Mk2/2b) coolant fan problem

[M Hawk]

Hi guys, just new here

Got a problem with my coolant fan on my mk2 punto. It comes on after about ten minutes of driving and runs constantly until I turn off the engine, even then it runs for about half a minute. Any ideas what the problem could be?

 

[Brendan W]

The car could be overheating or undercooling. Normal forward motion is supposed to be enough to cool the motor but the fan is there as back up if things are not going to plan such as stuck in traffic on a hot day or the thermostat sticking closed or close to it and preventing the hot water getting to the radiator in sufficient quantity. The fan will stay on even after shut down to cool the car to a safe level.
Has your car got a temperature gauge and is it drifting above the middle.
I would check the coolant level when the car is cold and top up as required. If the level is reasonable and there is no watery gurgling sound in the dash at startup I would suspect the thermostat is sticking.

 

[M Hawk]

Thanks for the reply Brendan.

The car hasn't got a temp gauge and the coolant level is ok. I am also pretty sure hot water is getting to the radiator as the top and bottom hose get hot when car is running. I have also tried replacing the fan relay but the fan still cuts in and doesn't go off like it should.

 

[atom0007]

It really depends what sort of driving you're doing. If you're creeping through town, it will be on a lot in summer. Staying on after engine off is normal.

In other words, are you sure you have a problem?

 

[M Hawk]

My concern is not really the fact the fan is staying on after engine is off but that it comes on so regularly while driving. When I got the car about a month or two ago the fan would only come on when the car was was sitting in idle for a long time, even then it would cut in and out as normal (not running constantly) and it was the same with my previous car which was also a punto. Now the fan just runs constant which will probably wear the fan out eventually and may lead to other problems.

 

[atom0007]

You may want to try flushing the radiator, if there is a flow restriction, cooling is less efficient. Also check thermostat is opening fully and not throttling flow. After that I'd worry about water pump.

 

[Ziggy122]

Some punto's
Mk2 asfaik - Allow the fan to keep running for a short period of time AFTER engine off, like my old mk2

But my mk2b - soon as i switch engine off- the fan also goes off

If the fan is kicking in after 10mins, i might suspect CTS failure

But i'd have to watch temp guage on FES to diagnose it really

Ziggy

 

[M Hawk]

Got a feeling it might be the CTS, got a new one ordered anyway so will try replacing that.

 

[crazyfrenchbird]

I had the same problem on my MK2b 2003 punto 16v.... in order to avoid any further damage to your head gasket I would suggest you get a new CTS (coolant temperature sensor about £8), new water pump and timing belt £60, new thermostat as well for about £16 and get them all fitted properly by a mechanic who will also clear the system for air bubbles.... it has happened to me on both my old punto 8v and my new one 16v and failing that you could risk damaging the head gasket although if the cooling fan comes on you should be fine but all these things are very much related... good luck

CFB

 

[atom0007]

I'd go for a slightly more measured approach, although the end result might be the same

 

[M Hawk]

Does anyone know the location of the CTS? Been looking for it but cant seem to find it.
Its an 8 valve engine I have.

 

[paulomk2]

it looks like a big metal bolt atached to the radiator with an electrical plug.

 

[Gibbons94]

This has recently just happened to me. The bearign went in the fan and caused it to mess up..costing me £150 for a new one