Hello, have a 01 windstar had p0303 code did a tune up because it hadn't had in 107k still code thought I checked the coil right so seemed ok. Then swichted #3 and #6 inj. to see if it would change no change. Said ok i'll take coil off and test again faulty coil with crack underneath, buy new coil install and try p0303 gone but now have p0304, p0305, p0306. changed plugs now got p0305,p0306, checked for spark with spark tester found ok. Now what? I don't think it's a spark problem.:banghead:

You have new high quality plug wires? Try swapping wires from coding cylinders to non coding cylinders to see if error code follows the wires/leaves the coding cylinders. Verify you have a solid ground for the coil. I give up. I'd also recommend using the "search this forum" just above your first post, looking up the p0301-6 codes to see what others did. I have read some but can't think of something more than what I suggested.