I have a 1998 toyota sienna with 132,000 miles on it. Recently I noticed a "shuddering" or hesitation while driving that was intermittent at idle and driving. The check engine light came on shortly thereafter and the code was p0303 for cyl #3 misfire. I suspected bad spark plugs cuz they were due for a change so I changed them all. It was fine for 2 days then started again today. I suspect plug wires but they don't look worn. Any help?

My name is Jerry Tiet. Base on my experience on 1998 Toyota Sienna with the DTC P0303 show there is a misfire in cylinder #3. a possible cause is the ignition coil of the #3 cylinder. Compare the resistance value of the ignition coil of cylinder #3 with the other coil or simply switch ignition coil #3 with one of the other ignition coil and clear the DTC with the scan tool. Then run engine for couple days. If the check engine light on again. Let me know what is the DTC code.