Hi all, Newbie here.
Just had a question regarding the cooling system pressure. I have a 1996 cav 2.2 OHV. The car is NOT overheating or anything like that, I replaced the pressurized cap because it was bad. After running the car up to operating temp, I checked the hoses and they seemed to have no pressure in them. Yes, I squeezed the hoses by hand, not that I do it all the time, it was just this once, honest. LOL. The upper radiator hose was hot, and the lower hose was cool or slightly warm. Yet, neither one seemed to have any pressure to them. They were both soft. So, am I correct to assume that the thermostat is stuck closed, if so why is the car NOT overheating ? I'm guessing it is stuck close because of the different temperatures of the hoses when I felt them by hand. Also, would I see the coolant circulating if I had the reservoir cap open, like you can see if you had the radiator cap open on those equipped with one, like the radiators with the filler necks. Any advice would be greatly appreciated. Thanks
Andy

The upper one is hot because it is carrying the heated engine coolant to the radiator. The bottom one is cool because it is carrying the cooled radiator coolant back to the engine. The engine makes the water hot, the radiator cools it down. If your temp gauge is reading in the normal area, then you do not have a bad thermostat.

Hey, thanks for the info. That makes sense. Yes, the temp gauge does read normal. But I was also wondering about the pressure in the hoses. Shouldn't the hoses be hard. Mine are soft, there doesn't seem to be any pressure build up in them. This is my first j-body, I know with my other cars the hoses were hard when squeezed because of the pressure build up. I already replaced the pressurized cap on the reservoir because the old one was not holding pressure, and still no pressure build up. Any thoughs on that ?
Thanks

try taking your cap off and put your hand over the resevoir and see if you can feel any pressure building up on your hand...its possible that you have a leak somwhere or maybe an air pocket in the system......not a mechanic, just some thoughts.




Cavalier z24......A poor man's Camaro....close enough, right?

Hey, thanks for all the helpful info guys, I really appreciate it. I neglected to mention that my check engine light was on. It was a code "P1133" I repalced the oxygen sensor in the manifold, reset the comp. and gave it a good run to heat up. Before the new O2 sensor, the cooling fan ran all the time. After the install of the new sensor, the fan did not start on engine start up. It did kick in when the engine got warm enough. And, what'd ya know. The cooling system now has the proper pressure in it. DUH, brain fart for me. But I do really appreciate all the input. Thanks a lot guys.
Andy