1999 Grand Caravan had been jerking and popping when going up hill. Spark plugs have about 20k on them. I replaced the coil pack last weekend and everything seemed fine. No problems at all until today. Going up hill again resulted in a bucking and about 3 pops (backfires).

Any idea what to check next? This van has 200k on it and just need it to last for 1 more year

 

Was the coil changed because of the jerking or did the jerking start after the coil pack change? Check engine light? Codes? Which engine?

 

Coil was changed because of the jerking. Thought process was the plugs and wires had 20k on them, and the coil had 200k. Jerking started very subtle but became really bad in about a month's time. That's when coil was replaced.

Jerking went away totally for about a week, but now is coming back. Not bad yet but if you pay close attention you can feel it when going up hill. We will see if this worsens over time.

Engine is the 3.3 Flex. No Check Engine Light. I only checked codes by doing the key dance, and nothing came up.