Senerio...
Start cold idle fine for 20 seconds, drops down to almost stall for 20 seconds, recovers then fine.
Take off driving normal ....driving on freeway get to 75 mph...car starts bucking and missing back to 70mph.
15 minitues later excellarate straight through to 85 mph no issues.
A by ideas on what this could be.
THANKS for suggestions.

 

Can you tell us anything else about the car? This being the "general tech" section, I don't know whether to tell you to look for stored codes, or ask when was the last time the carburetor was cleaned.

 

2002 vert. 3.8 to 4.2 conversion
windstar intake, 70mm TB, cold air intake,dual exhaust, new fuel injector and fuel pump.
keep throwing cmp..ckp...sync code