Just a quick question about the cooling fan.

When the car (MY93 WRX) becomes stationary the cooling fan (both of them) comes on almost immediately, about 15 seconds. The temp needle during normal operating is about in the middle of the gauge. This moves only slightly before the fan cuts in, such a small movement that without looking closley it seems not to move.

The fan does not then cut out, while idling stationary the fan stays permanently on. If you go for a quick drive it cuts out.

Is this normal? Other cars that i have owned the cooling fan would take some time to cut it and would cut in and out while idling stationary.

Anybodys car also do this?

Tone.

 

The fan should cycle on and off over time... it may just take longer than you assume... certainly, the fact it cuts out when you are on the move implies the temp sensing system is ok. If you come to a standstill after thrashing the car the engine will require a much longer burst of fan to bring it down to the required temp.

Moray

 

Is your climate control or air con switched on all the time ??? try switching it off, as the second fan is only installed on cars with CC or A/C

 

I have a 94 WRX which also gets hot and the fan comes on a lot (but not continually).

I put some "WaterWetter" in the coolant and this has reduced it.

Maybe worth considering...

Thanks

Gavin

 

Thanks for your replies,

Ian, the climate comtrol is off (or the light is off anyway, i'll give it ago with the light on ,see if it make a difference) but both fans are on. I've read before that only one should be on, strange!

Gavin, its due for the 60 000 mile service soon (i.e coolant change time) and i'll give the water wetter a try. The coolant does appear to need changing, its quite dirty. This could contribute to the higher temp therefore the fan cuts in sooner? This still doesn't explain why the fans do not cut out while the car is stationary. I waited over 15 mins once but it still didn't cut out!

Moray, the fan comes on almost immediately even if i've been drving it like an old age pensioner, i.e only 2000 rpm. I agree that the temp sensing does seem ok as the fan goes out while on the move. What does your temp gauge read during normal operation. I'm thinking that my coolant is so dirty and contaminated that it is continually running a little hot and so the fan cuts is very sson and the fans donot give sufficent cooling to reduce the temp below the cut in point?

Anyway, thanks again.

Tone.

 

My engine temp gauge doesn't really vary visibly, but I can check the engine temperature on my data-log traces to monitor what happens. I do have an oil cooler fitted, but that isn't doing much when stationary.

 

Is the coolant a specific colour ?

If it has the correct amount of anti-freeze in it, it should be a distinct colour (mine's green).

If it were my car, I would get the coolant drained ASAP if it is dirty. Impreza's run very hot anyway and the coolant is used for the engine and turbo.

Should be a fairly simple DIY job as long as the car is stone-cold when you do it !

Thanks

Gavin

 

Gavin,

The coolant is a sort of orange colour, i know this because the top hose split last week and dumped a lot of it on the bonnet and the side of the radiator. Its left a lovely orange residue.

I'm definately gonna get it changed as soon as pos.

Hope it irons out the probs with the ccoling fan.

Cheers,

Tone.

 

Tone

I don't want to worry you unnecessarily but you often get the symptoms you describe when you have a weaping head gasket.

Coolant loss is another symptom of this problem,do you have to top up the water on a regular basis even though there are no obvious leaks?

If so it may be worth getting it checked out by someone in the know.

I think it is unlikely to be this but it is something to be aware of.

PS get that dirty coolant changed because, among other things,it will have lost its corrosion inhibiting properties

 

Andy,

When i had the top hose replaced the system was pressure checked so it should be O.K with regards to the head gasket (God, i hope so, you've given me anthor thing to worry about on my ever growing list ).

What i did notice (before the hose split) was that the level in the radiator feed (the black tank of the left side of the engine, forgive the poor terms i'm not sure the correct one) was always fine but the small coolant pipe on the front right side of the engine would have to be constantly topped up. Why does the car have two top-up points? and what does the one of the right had side (i.e small pipe with yellow top) actually do?

Any expanation of the general cooling system workings would be gratefully received (i know how a cooling system works i.e thermostat .. etc, i mean particular to the impreza engine).

Thanks,

Tone.