I picked up a 98 GT convertible last week pretty reasonable knowing it needed a little work. 85,000 miles, stock 4.6 manual trans car, with a cold air intake, headers and no cat exhaust. The intake manifold is the original and has the standard crack at the coolant passage. Going to replace that but in the meantime, it also stumbles on acceleration. Especially when cold but even warmed up it will still stumble at acceleration in 1st and 2nd gear. I can't imagine the coolant leak on the intake would cause this problem. No codes. At 3rd gear on up seems to be fine. I'm thinking possibly MAF but any other suggestions? Thanks!