I have a 2009 vw rabbit with the same engine and there's a second coolant temperature sensor on the lower radiator hose, driver side. How do I replace it without loosing a ton of coolant. Will the air get into the system?
Removing the coolant temperature sensor on the lower radiator hose you will lose a majority of the coolant. I would jack the car up and use a clean bucket and remove the lower cooling hose hopefully catching most the coolant. Once drained ,you can then replace your coolant temp sensor and reinstall the hose. YES, to bleed the cooling system, leave the car on the jacks so the the coolant tank is the highest point in the system ,take the coolant tank cap off and start the car .While the engine warms, it will "burp" all the air trapped in the system through the coolant tank, watching closely the cars temp as it rises, to make sure the engine doesn't overheat. At some point the coolant will be so hot that it will start to boil out of the coolant tank, then put the coolant tank cap back on.Once the engine cools down repeat if needed, until no air bubbles are seen in the coolant tank and the engine temp is stable.
I have a 2009 vw rabbit with the same engine and there's a second coolant temperature sensor on the lower radiator hose, driver side. How do I replace it without loosing a ton of coolant. Will the air get into the system?
Removing the coolant temperature sensor on the lower radiator hose you will lose a majority of the coolant. I would jack the car up and use a clean bucket and remove the lower cooling hose hopefully catching most the coolant. Once drained ,you can then replace your coolant temp sensor and reinstall the hose.
YES, to bleed the cooling system, leave the car on the jacks so the the coolant tank is the highest point in the system ,take the coolant tank cap off and start the car .While the engine warms, it will "burp" all the air trapped in the system through the coolant tank, watching closely the cars temp as it rises, to make sure the engine doesn't overheat. At some point the coolant will be so hot that it will start to boil out of the coolant tank, then put the coolant tank cap back on.Once the engine cools down repeat if needed, until no air bubbles are seen in the coolant tank and the engine temp is stable.