[shorod]

When you feather the throttle, does the engine then seem to run okay, or is it rough?

The V-6 SHO engine has issues with leaky spark plug well seals that would allow oil to flow into the spark plug wells and cause the spark plug wires to short to the head and cause a misfire.

If the fuel has been sitting in the car for quite some time, there may be varnish on the fuel injector nozzles as well. You may want to add a bottle of fuel injector cleaner to the tank and run it awhile, after checking at least the front three plug wires for signs of moisture or oil.

-Rod