My 99 ranger has a strange issue its got a miss when the A/C is on, when going down the road I can feel the engine sorta pulse for a second, gets better the more I drive it, its got all new plugs and wires, not sure where else to look, any ideas? Thanks

 

If the problem goes away with the A/C off, you are likely feeling the A/C clutch cutting in and out. I notice it on my '99 Ranger, 3.0 V-6.