Car is Bucking... I need Help please

[mwhite]

1993 Lincoln Towncar 4.6 v8...I had a coolant leak and the manifold needed to be removed (5 hours of labor) they replaced the manifold gasket and a water tube. The car was fine for about 2 days it is now bucking and running very rough. The mechanic is on vacation this week. spark plugs seem fine. I do have a vacuum like noise (before this repai) when i step on the gas it goes away. There is no pick up no with this bucking....wiring??? plugs???
thanks
margaret

 

[kustomizingkid]

I would pull the plug wires and blow out the plug wells, some coolant might be down there causing the plug wires to ground out giving you a misfire...