FYI - I don't believe the '06 Monte had a 3800. That being said, it won't have coolant elbows.

When checking if you are low on coolant, when the car is cold, open the cap to the radiator itself and peak inside.

The water flowing noise under the dash could be a small air pocket (I've heard it before on some cars, but it never was linked to any temp related problems).

When the car heats up, does it ever get to a point where it heats up enough for the fans to kick on? If not, my guess would be you have a bad t-stat that is stuck open.

If it's not a t-stat, then my next two thoughts/guesses:
- Clog in the heater core
- Problems with the actuators that adjust the flappers/dampeners inside the HVAC module

I used to work with a guy who had a GMC Envoy and his actuator was messed up. Somewhere on the Internet, he found a method that "resets" the actuators and it went back to normal. Being a GM, that might work on the Monte as well. Unfortunately, I don't know what that process was.

 

Jason thats the second time today you caught me with getting the wrong car. I was thinking 2005 lt. haha its been a long day 15 hours.

 

No worries man. It's all good. Trust me, we've all made those mistakes.

 

Lol that's why I asked if he had ticking. If he does it's the acurators, pretty easy to change.

 

definitely sounds like your water pump gasket. common 3500 problem. water pump is on the accesory drive, bottom right hand corner of motor on passenger side. take the belt off and its about 8 bolts. pretty easy. i replaced the whole pump but i wish i had just done the gasket, thats all i really needed and couldve saved some money. oh well. good luck.

 

where r acurators located

 

2x Thermostat. Keep coolant/antifreeze full in cold temps.

 

any one out their put a heater core in a 06 monte carlo does dash have to come out