I made the following post back on Oct. 4, 2004. Sounds like we are having
the same trouble. I rarely drive the car but was looking at buying a fuel
pressure tester from NAPA for about $45.00. Let me know what you find out
94 Pontiac SSEi.
The car is showing a miss on the #5 cylinder, occurs only when engine is
under boost from the supercharger. Occasionally also shows miss on #4 and
less frequently on #6. This was found by using a scan tool.
Have swapped plugs, wires, injectors, injector wires, and coils with those
from either #3 or #1 cylinder, but problem stays on #5. Also tried a new
ignition control module. Engine runs smooth in the driveway at all rpms.
Only misses under load and only under boost conditions.
I'm thinking fuel pressure regulator?? fuel pump??
The fuel filter was recently replaced. I run 92/93 octane.
Problem occured after car was parked for several months with only being
started every couple of weeks and idling to operating temp. The car has
177,000 miles. Ran great before parking it.
Any help would be greatly appreciated.