'97 F150, knocking & surging when cold.

Got a '97 F150 with V6 that knocks and surges when cold. After warm up 2- 5 minutes it smoothes out and is OK. Any idea's??

sounds like the knock sensor is out of it.

I had knocks too when cold in my 97 6cyl but not surging, turned out to be catalytic converter, had it changed now its fine.

I had knocks too when cold in my 97 6cyl but not surging, turned out to be catalytic converter, had it changed now its fine.
HAD THE SAME PROBLEM WITH MY 97 4.2 AT 15000 MILES THE PLUGS WERE FOULED OUT AND THE ENGINE COMPUTER HAD TO BE REPROGRAMED