Been getting a PO307 misfire code lately. Opti,plugs,wires,ignition coil and that #7 injector has been replaced. I replaced the plug wire with another one and I still get the same code. I have noticed that here lately that my coolant level is dropping and that makes me think that I may have a bad head gasket.Would this cause this problem? The car will run fine for a day or two then it will stumble for a second then I get the code.

 

Checked the exhaust and I have some white smoke,but I don't smell antifreeze. I do here a puh,puh,puh,puh sound from the exhaust.(hope that makes sense) I also noticed some condensation inside the exhaust tips. It's around 50 degrees here and the car is at operating temp.

 

Uh oh. I checked the oil cap and I have what appears to be dried chocolate milk in the cap. I also saw yellow looking foam in the oil fill neck. Could this be antifreeze eventhough dexcool is orange?