Q: What could cause loud clicking/clunking sound from front. Temp gauge fluttering

Hi There, it sounds like you may have two separate issues going on here. The clicking/clunking noise sounds like a bad CV joint. A CV (Constant Velocity) joint is a shaft that connects the transmission to the wheels, essentially transferring the power from the drive train directly to the wheels. The CV joint is packed with a special grease and sealed tight with the rubber or plastic boot, that is held in place with two clamps. The most common problem with the CV joints is when the protective boot cracks or gets damaged. Once this happens, the grease comes out and moisture and dirt get in, causing the CV joint to wear faster and eventually fail due to lack of lubrication and corrosion. When the CV joint becomes damaged or worn, you may hear a clicking, clunking or popping sound coming from this area as the weight of the vehicle puts pressure on this area and shifts back and forth and side to side.

The temperature fluctuation is a result of some part of the cooling system functioning properly. Overheating can be caused by a number of things such as low coolant levels, a faulty thermostat, a clogged radiator or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. You may also have a water pump that is beginning to fail. Water pumps often times will begin to produce a bit of a whining sound when they are starting to fail. A common problem also associated with this is the water pump may begin to leak around the water pump shaft due to the seal being damaged. In addition to leaking around the pump, you may have a leak elsewhere in the cooling system coming from one of the hoses going to or from the radiator. Lastly, you may have a failing cylinder head gasket allowing coolant to leak from the water passages into the cylinders resulting in the coolant being burnt in the combustion chamber with the fuel. If this is the case, you may also notice a bit of white smoke coming from your exhaust which is a product of the coolant being turned into a steam like vapor. I would suggest having an expert from Your Mechanic come to your home to diagnose and inspect your vehicle.