Hey wishihadatalon,

When you replaced your sensor and T-stat, did you need to drain/refill any coolant? I've got the same issue and am planning to do this soon.

 

You do have to drain a little bit but I just watched the amount in the resivoir and when it got to the bottom, I closed the valve and started working. Draining the coolant is very very easy to do, you just need a 13mm deep socket and there is a hole on the drivers side spalsh guard right behind the bumper. I just freed it up with a ratchet, then took the ratchet off and used my fingers to twist the socket. This allows he coolant to go right through the socket and down to your drain pan.

 

Only going by your own explanation, Wish:

"I took an hour long drive today and it took nearly 45 minutes for the gauge to move. Then all of the sudden it went straight up to temp which is pretty much opposite of how a thermostat operates. I hear my fans oh high when I key the car on and after I turn the car off. Also my heat is very very poor."

To me, that means no circulation at speed, because the water pump isn't turning well. The impeller shaft just spins without turning any fluid. No circulation through the heater core means no heat.

Then, you stop at a light. The slower RPM's make it easier for the impeller system to "stick pressure and seal," initiating circulation and causing both the temp gauge and the heater to wake up immediately.

That, to me at least, is textbook symptomatic water pump failure. If you were able to fix this issue with a t-stat and a sensor... you are a luckier man than I. Since your car's engine is still running well, I have to assume that is the case.

 

From what I have experienced, most water pumps just FAIL or leak before they FAIL. If a water pump is bad and coolant is not circulating, the car will heat up REAL FAST, then OVER HEAT. Usually a water pump shaft or impeller will break since these pumps DO NOT HAVE CLUTCHES to my knowledge. They are direct drive as far as I know. I could be wrong. If the impeller spins, it is circulating coolant.

I purchased a 960 with a broken water pump. I picked up the car with the outside temp at about 34 degrees. I had my Scan Gauge II connected to drive home and while driving it back to the house it warmed up real fast. The motor temp was running a little high (225) at idle, running hot (255) at 50+ mph. Fairly ok when going down hill at 45 mph (215), but never got below 205 the entire 20 miles back to the house. I got a little nervous when I was going up hill at 50 mph on the freeway, it got up to about 265 degrees. The impeller was broken off, lying in the motor.

I would replace the thermostat only if I had warm up problems then go from there if the problem wasn't fixed. Most thermostat get weak before they fail. What I mean by that is, your car will take longer to warm up if it warms up all the way. It will run at 155 degrees instead of 185 degrees.