Strange issue. I recently picked up a 1999 max SE for relatively cheap. The rad was low on coolant, so I topped it up with the engine running, and all seemed well. The car had little heat at first, but once I filled the rad, it came back.

My problem is this:

With the car running, and the rad cap off, I don't get the bubbling that I'd normally get when I rev the engine a bit. Supposedly the car had a new rad put in just before I bought it (it does look new). I have yet to see the rad fans turn on to. The car does not overheat. I also find it strange that when I squeeze the rad hoses, the coolant doesn't rush to the top of the filler neck like is usually does on my other max's. Any ideas?

 

Might need a new thermostat...is the heat only kinda warm but not hot...thats a signt eh thermostat is stuck open

 

The engine was at full operating temp, and the heat was pretty warm. Not as hot as if the car was in motion, but still pretty warm.

 

Check the upper and lower radiator hose at normal operating temp. If one feels hotter than the other, your thermostat is no good.

 

I'll check that tomrrow. I'll be relieved if it's only the thermostat....I have an extra one kickin around here at home.

 

Is it leaking any fluid?? any blue plumes of smoke out the exhaust??

 

if i remember correctly, you need to bleed the air bubbles out of the system in the 3rd gens to get the heat working correctly. Not sure if it also applies to 4th gen as i've only heard of it on the 3rd. To purge the system from bubbles, anyways, to bleed the air bubbles simply pakr your car uphill, start the car, and top off with radiator fluid. At least this was what i was told with the 3rd gens. Since its the winter, it'll be easier to tell. Once the car is warmed and you start driving, does the temp needle go down when you start moving and go back up when you stop? If htis is the case, your thermostat is stuck open.