UK-POLOS.NET - THE VW Polo Forum

wel seeing as my car isalways running cold only until i stop in traffic i decided to change the thermostat today, removed the housing ony to find i had no thermostat anyway lol, fitted the one i brought from the motor factors topped the water up and started her up, the gauge quickley got to the normal position pointing straight up so i thought everthing was fine, went out this afternoon to swindon from oxford about 25 miles or so and the guage stayed exactly thier, go into swindon and the gauge was rising slowly it made it to 110 so i stopped, and took the cover off the water reservior very carfully which was steaming violently and bubbling over, i let the car get cool and topped the water back up again and had the same problem on the way home, it made it to normal then slowley krept over so called the aa, they came out and did a few tests with tools that looked like penis enlargers lol, he checked that thejr was no exshaut gasses in the water pressuming the head gasket had not failed and that their was no air in the system, also checked that the fan kicked in around 80, also checked that the thermostat was opening correctly and it was, pulled away again and a mile down the road it did it again, he said he rekund it might be the water pump not pushing water round fast enough and that i should get it towed home, but i just got him to take the stat out and i went all the way home perfectly fine but just running cold again lol, anyone got and ideas as to wht it coud be?

It could well be your waterpump failed or failing, as pressure is required to force it past the thermostat as its spring loaded.

Check the plastic part that the thermostat pin pushes against. Most likely that has broken.

Broken or stiff... dead cheap to replace... think its under £20 fro French german sweedish... Its a fiddly thing to replace but not that hard!

i havfe changed the houging the lil hole that the pin from the stat sits in had pushed right through, got a new housing and changed it with a new stat but the car still stays dead cold when moving and warms up nly when i stop for 15min, i know their is def somthing wroong as my gf has a 97 polo and her temp gaage stays in the middle whilst blasting it down the morotway

gharbud wrote:i havfe changed the houging the lil hole that the pin from the stat sits in had pushed right through, got a new housing and changed it with a new stat but the car still stays dead cold when moving and warms up nly when i stop for 15min, i know their is def somthing wroong as my gf has a 97 polo and her temp gaage stays in the middle whilst blasting it down the morotway

Seems like the pump is playing up or dead, the standard temp on the polo should be 90c if any higher try not to drive it as your overheating the engine, which means your causing the oil to break up, this will cause sludge and harm your engines life. So an oil changed will be highly advised after its fixed, just my two pence.