How to Replace the Thermostat in a 1994 VW Jetta

Iskandar Blogger 9:28 AM
How to Replace the Thermostat in a 1994 VW Jetta

When the thermostat in your 1994 Volkswagen Jetta fails, you'll feel fortunate that it failed in the open position. This prevents your Jetta from overheating and causing thousands of dollars in engine damage, but it won't do a lot for keeping you warm in cold weather. You don't have to let your car sit for a week until a mechanic can get to it; pick up a replacement thermostat and complete the job yourself.

Instructions

    1

    Locate the Jetta's thermostat housing at the top of the radiator and disconnect the radiator inlet hose from the housing. This is done by loosening the band clamp that holds the hose to the housing with a screwdriver. Once the hose is loosened, pull it off the housing.

    2

    Remove the two bolts that hold the thermostat housing onto the intake manifold. Some radiator fluid will likely spill out of the housing. This is common. To avoid burning yourself, this job should be completed when the Jetta engine and coolant have had plenty of time to cool.

    3

    Remove the old thermostat housing gasket. It should pull off in one piece, but it is not uncommon for Volkswagen to seal the gasket with PVC gasket maker. If this is the case with your Jetta, you will need to scrape the old PVC gasket away. Take caution not to get any PVC into the housing, which could cause the new thermostat to malfunction.

    4

    Remove the thermostat from the housing by pulling up on it. There are no bolts to hold it into place. It sits on a recessed lip machined into the inside of the intake manifold.

    5

    Insert the new thermostat, making sure it is oriented with the correct side facing up. Place the new thermostat housing gasket in place and bolt the top of the housing back onto the intake manifold with the bolts you took off earlier.

    6

    Push the radiator inlet hose back onto the thermostat housing and tighten the band clamp securely.

    7

    Start your Jetta's engine and monitor the inlet hose and gasket area for leaks. If the hose leaks, tighten the band clamp tighter. If the gasket area leaks, remove the housing and apply a new gasket and a small amount of PVC sealer. Then monitor for leaks again