1997 pont gr prix 3800. 12/23/14 new intake manifold gask & water pump.
still ran good cold but same cyl 5 misfire when normal operating temp. repair shop replaced crankshaft position sensor. now it sounds like the valves or something, or like the timing is off. did he do something wrong or do I now have a new different problem? any ideas would be appreciated.

sometimes the coolant fouls the plugs