I have an '02 VW Jetta with the 2.0L 4 cylinder, and I've had the car for just over a year. Throughout this time, the temp gauge has pretty much remained bottomed out. Very rarely, it will sneak up to 190ish degrees for a little while (less than a couple of minutes), and go back down again. It's done this in the hottest parts of summer, and in the winter as well. I've checked the hoses, and the upper hose will be warm/hot to the touch, whereas the lower hose (going to the thermostat housing) will remain relatively cool.
I thought it may be a stuck t-stat, so I changed the thermostat out today and flushed the cooling system with Prestone SuperFlush. During the first flush, with the Prestone and water in the radiator, the temp did get up to 190* and stayed there while I was driving, so I let the heater run for ten minutes. I then flushed the system with pure water, and it never got up to temp. I drained the water out, and filled with the correct 50/50 mix, and I'm still not getting the temp gauge to budge.
I'm afraid I have air trapped in the system, as my upper hose remains hot to the touch (roughly 145*) and the lower hose is cool. I've checked the temp of the block at various places with an infrared thermometer, and it averages 170ish degrees. How can I purge the system of air, if this is my problem? These cars don't have a radiator cap, just a cooling reservoir. I filled the radiator up via the upper hose, and took my time doing so to allow air to "burp" out (took about 30 minutes). I've watched the fluid level in the cooling reservoir, and its getting to 145*, but the level isn't changing. Any ideas?
I thought it may be a stuck t-stat, so I changed the thermostat out today and flushed the cooling system with Prestone SuperFlush. During the first flush, with the Prestone and water in the radiator, the temp did get up to 190* and stayed there while I was driving, so I let the heater run for ten minutes. I then flushed the system with pure water, and it never got up to temp. I drained the water out, and filled with the correct 50/50 mix, and I'm still not getting the temp gauge to budge.
I'm afraid I have air trapped in the system, as my upper hose remains hot to the touch (roughly 145*) and the lower hose is cool. I've checked the temp of the block at various places with an infrared thermometer, and it averages 170ish degrees. How can I purge the system of air, if this is my problem? These cars don't have a radiator cap, just a cooling reservoir. I filled the radiator up via the upper hose, and took my time doing so to allow air to "burp" out (took about 30 minutes). I've watched the fluid level in the cooling reservoir, and its getting to 145*, but the level isn't changing. Any ideas?
