right yesterday my coolant light started flashing when i was driving, so i pulled over to check the level, it was like 20mm over 'max' (checked it this morning when cold and was perfectly on 'max') but i am not sure what this is? i am guessing it is just the plug which goes in the top of my coolant tank, so hopefully off to the scrappy tomoro to see if i can find some spares to test them out! but twice it has been fine for a while! yest i parked up at a vw shop to collect a part and after that i am sure it was fine till i got home and used the car again! and today i filled up with petroel and after i turned car back on to go home about 5 miles it was fine!!?

so really confused to what it could be!

the polo manuel says it could be the fan fuse, so just checked that and the fuse is fine!

polo g40 engine in a gt shell, done 8500 miles with the conversion and only time it has ever come on!??!?

if you need any more info and any help would be greatly appreciated! i hope someone on here has had the problem and can tell me ehat they done to resolve it lol

Many thanks ben xx

A couple of points here: The maximum mark should be the level that the coolant is at when the engine is hot ( coolant expanded) minimum mark is what it should be with engine cold (coolant contracted) But don't worry overmuch if it is a little high all the time. If you were to fill the expansion tank to the very top when the engine was cold, what would happen would be that as the engine warmed up and the coolant expanded, coolant would be pushed out of the pressure regulating valve in the expansion tank cap.

The other point you probably know anyway, the coolant warning light is a dual affair which tells you either that the coolant level is low or that the engine is overheating.

If you are unsure, keep an eye on the temperature gauge, if it stays on normal (about 90 degrees) and the light comes on, it is probably a TEMPERATURE sender fault, rather then a level sensor fault.

Regards and a happy new year.

A couple of points here: The maximum mark should be the level that the coolant is at when the engine is hot ( coolant expanded) minimum mark is what it should be with engine cold (coolant contracted) But don't worry overmuch if it is a little high all the time. If you were to fill the expansion tank to the very top when the engine was cold, what would happen would be that as the engine warmed up and the coolant expanded, coolant would be pushed out of the pressure regulating valve in the expansion tank cap.

The other point you probably know anyway, the coolant warning light is a dual affair which tells you either that the coolant level is low or that the engine is overheating.

If you are unsure, keep an eye on the temperature gauge, if it stays on normal (about 90 degrees) and the light comes on, it is probably a TEMPERATURE sender fault, rather then a level sensor fault.

Regards and a happy new year.

cheers mate, the temp on my gauge is fine, not overheating on there one bit! it is kind of as random as can be with the light coming on! sometimes car has been on for a few minutes when been left over night and it will come on then lol!! so i am guessing it is proberly the sensor!

on the mk3 polo g40 i have a blue and a black sensor in the thermostat housing which are the temp sensores i believe? i am not sure if they both are but do you know which one is and i will try replacing that!! hopefully have sourced some second hand ones from here so with a bit of luck that will sort it !

thanks ben x