Why would there be gouges/chunks missing at the top 1/4" of the cylinder #5 wall, while this doesn't exist in the other cylinders? Could that be caused by an excessively lean mixture in that cylinder? If so, what would cause this in that cylinder only?
I've heard the injection pumps on these cars are frequent causes of trouble, and it is possible that the part of the pump responsible for cylinder #5 is bad. Is it true bad injection pumps are indicated by a rocking movement during idle? Is it also possible the injector is clogged for cylinder #5 causing it to be lean?