Fan kicking in all the time at idle.

[mrwookie]

Right folks having an annoyingly niggly issue with my LCR and as cooling is not my strong point hoping someone can offer up some advice.

If I take my LCR out for a drive over say 20mins and then come home and let it cool down idling, the fan will kick in even through the temp gauge is sat rock solid at 90 degrees C. When the fan kicks in it will cause the temp to creep up to about 100 degrees C but as soon as the fan stops drops back to 90. Does this every 2-3 mins when sat at idle.

Did think it was because of the hot weather but has done the same on the few cooler days we have had recently.
Also noticed another slightly different whistle when coming on boost but don't think its related or atleats hope not....

Also had new turbo and head gasket in April/May 09

Air pocket or faulty thermostat???????

Any thoughts...???

Cheers

 

[Gubien]

If you have aircon on its normal behavoir, mine does it too! If it's on, try turning it off, they the sucker stops

 

[AMR_RM]

If you have aircon on its normal behavoir, mine does it too! If it's on, try turning it off, they the sucker stops

If you have your air con on the fans will turn at low speed, if they are on off at high speed, im affraid your fans are knackered and you will have to replace both or do the mod as detailed in a fan thread

Do a search for fans as this will bring up mega amounts of threads

 

[mrwookie]

Gonna say don't use my AC need every ounce of power........

 

[mrwookie]

Do a search for fans as this will bring up mega amounts of threads

Not sure it that is pointed at my problem as well but have done lots of searches and the dif with the issues I am having is the temp only rises when fan kicks in. Almost like its warming it rather than cooling.........

 

[Muttley]

Fans are worked by a thermal switch set in the radiator itself. The ECU has no control over the fans, the only thing that will switch them on is hot coolant. The dashboard gauge is fed from a sensor next to the cylinder head, in the same unit as the coolant temperature sensor that feeds the ECU (but separate from the ECU sensor). So the locations are different, radiator vs engine.

You have a hot engine and you are now sat idling, with no air movement over the engine or through the radiator. The heat built up in the engine components has to go somewhere, into the oil and water, and the temperature will rise, triggering the fans to blow air through the radiator and cool things down.

You have an FMIC which will obstruct airflow through the radiator and dump extra heat into it once the fans start. This may add to the problem. The fans will keep going until the water in the radiator is down to their switch-off temperature.


The only item I'd be worried about is your water pump, as it is possible that poor circulation is restricting the radiator's ability to cool your hot engine. However, water pump issues are normally seen at high loads on the motorway, not at idle, so that's a long shot.

 

[mrwookie]

Fans are worked by a thermal switch set in the radiator itself. The ECU has no control over the fans, the only thing that will switch them on is hot coolant. The dashboard gauge is fed from a sensor next to the cylinder head, in the same unit as the coolant temperature sensor that feeds the ECU (but separate from the ECU sensor). So the locations are different, radiator vs engine.

You have a hot engine and you are now sat idling, with no air movement over the engine or through the radiator. The heat built up in the engine components has to go somewhere, into the oil and water, and the temperature will rise, triggering the fans to blow air through the radiator and cool things down.

You have an FMIC which will obstruct airflow through the radiator and dump extra heat into it once the fans start. This may add to the problem. The fans will keep going until the water in the radiator is down to their switch-off temperature.


The only item I'd be worried about is your water pump, as it is possible that poor circulation is restricting the radiator's ability to cool your hot engine. However, water pump issues are normally seen at high loads on the motorway, not at idle, so that's a long shot.

Cool cheers mutley. As for the FMIC restricting airflow its been on since early Feb 09 and had soem hot spells in between but only started happening within last few weeks.

Water pump is 8 months, if that, and replaced with a metal impellor one but that that doesn't rule out an air bubble some where along the line.
Anyway of checking this??