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MG MGF Technical - Water Temperature

Hi

I own a 2001 MGF and today I have noticed today that the water temp rose into the red when at a standstill. Obviously I booked it in immediately, thinking that there was a thermostat problem, i.e. it had jammed after the cold patch we have just had, however has anyone had gauge problems with this before?

Regards,

Chris
Chris

If this happens only at a standstill, then I would suspect a dodgy cooling fan heat sensor or the fan itself (or the wiring between the two)
I'm sure the garage will sort it in no time.

Mike
Mike

Chris,

I agree with Mike. This seems to be a fan not coming on problem. Can you hear the front radiator fan when you leave the car on idle for a while? I assume the temperature returned to normal as soon as you started moving. I would think it's a loose connection to the fan or the sensor that turns it on - your car is very new for this sort of thing to happen though, the dealer should sort things out. Did you check the coolant level? Maybe you lost some through the cap when the engine overheated.

Cheers
Spyros
Spyros Papageorghiou

This sounds exactly like the sensor failing, or the connection to the sensor corroding as has happened on my car 3 times now. Easy to check and fix in both cases. If you take it to a dealer they will replace the sensor which will cure both problems, for now. But if it is corrosion of the contacts you will have the problem again in a year. The fix is easy. Takes 30 mins and doesn't cost anything.

Lift the back end of the hood, remove sound deadening etc and remove the engine cover. At the front of the engine sort of halfway down the block is the brown connector to the ecu temperature and fan sensor. The connector is held on with a wire clip. Prise the wire off then make and break the connection a few times. If you have any hifi connections cleaner use it on the sensor contacts. Replace connector and clip it back on. Replace engine cover and hood and test it all works by taking the car for a run then when good and hot leave it running on tickover. The fan should come on in less than 10 minutes even in the current cold weather. If the fan does not come on but you see the gauge move above it's normal just below halfway mark then almost certainly the sensor has failed. The sensor can be replaced by a garage in 10 minutes but you can do it yourself following the same instructions as above except unscrewing and replacing the sensor instead of just cleaning the contacts.

Whatever you do make sure you do something. Having the temp rise into the red is not conducive to a long and productive engine life. Rob Bells site has instructions on lifting the hood and removing the engine cover, and I am sure Dieter has pictures of the ecu temperature and fan sensor.

HTH. Alan
Alan

Hi

Thanks for the advice everyone..

When the car is idling, the fan does come on but this does not stop the needle rising into the red, which was what lead me to think it might be the thermostat.. but i am certainly no expert..

Cheers,

Chris

Chris

p.s. Alan, whats are the addresses of those sites you mentioned? I am new to this forum so apologies if this is detailed elsewhere already.

Thanks,

Chris
Chris

Chris
Rob Bells site is www.mgf.4mg.com and Dieters www.mgf.tech.here.de

You say the fan comes on. Be sure it is the radiator fan not the engine bay one. I can't hear my radiator fan if I am in the car, but the engine bay one being close is very apparent when working. If your rad fan does come on and you are still going into the red then something serious is happening and you need a dealer visit pronto.

Alan
Alan

Thanks for your help Alan, from what you've said it sounds like it was the engine bay fan i heard..

Anyway its at my local rover dealer at the moment as it is under warranty and they are taking their sweet merry time over it. Apparently when they tested it it was all over the place.. going high then dropping back down and all sorts.. Anyway they are waiting for advice back from Rover..

Chris..
Chris

http://www.mgf.4mg.com/hgf_diagnosis.htm

Is Robs, see for ECU Sensor.

Cheers
Dieter
Dieter Koennecke

This thread was discussed between 08/01/2002 and 14/01/2002

MG MGF Technical index

This thread is from the archive. The Live MG MGF Technical BBS is active now.