Engine Mechanical problem
1988 Mercury Tracer 4 cyl Front Wheel Drive Automatic 91,000 miles

On my 1988 Mercury Tracer wagon, it makes a loud pinging noise when you accelerate when the engine is hot. IT does not do it when it is cold but it is very loud when it is hot and it only happens when accelerating. Any ideas ???

The pinging is caused when the fuel mixture ignites prematurely and put extreme stress on the mechanical parts of the engine.
This can sometimes be caused by a bad tank of gas. You want to fix this problem quickly, otherwise you can cause severe engine damage.

Have the mechanical timing checked, this is done by going into diagnostic mode and setting the base timing by adjusting the distributor.