98 Stratus - overheats and pings on acceleration

Car info:
98 Dodge Stratus
Mileage - 148,527
Engine - 2.4L

I have certain problems that seem to be air-conditioning related or at least become more pronounced with the use of the air conditioner. During acceleration, especially uphill and if the air conditioning is on, there is a pinging, knocking, clatter sound (pick a word) that eventually goes away once I reach a constant rate of speed. That doesn’t appear to be the case when the air conditioner is off, at least it is not audible enough to hear (windows up and radio down) or my head out the window. I should also add that if acceleration is slow; which frustrates the people behind me the pinging is not there. I’m running the normal octane (regular unleaded) that the owners manual calls for 89, I believe. In addition if the temperature outside is 95 degrees Fahrenheit or above and again if the air conditioner is on; if I stop for any length of time (stop light) the temperature gauge climbs. Once the car is in motion temperature returns to normal. If I turn the air conditioner off the car will not overheat even if I stop for an extended bit of time with the engine running. With the air conditioner on the vehicle experiences a gurgling sound and it seems to come from the coolant bottle. To top this off the vehicle has been using large amounts of fuel. Service to date has been: timing belt replaced, water pump replaced, dealer plugs installed, radiator cleaned, thermostat replaced, radiator fans have been checked and apparently in working order and miscellaneous tune up items (filters, etc.). Any help will be greatly appreciated.