I have tried changing gas and it does not stop the pinging and rattling. I talked to the parts counter at our local Ford dealer and he told me to pull the negative cable from the battery for 10 to 20 minutes then run the car hard for 30 miles. Another said I needed a small gasket replaced. I purchased the gasket since it was only $2.50 but have not replaced it yet. I can't even remember what it went to. Just that the part sits back by the firewall.
Any advice out there? The car has lost some power and rattles A LOT with the car climbs hills and when you get on it.