Okay, I've got everything back together and took her out for a spin. About 10 miles into the test run I get the bucking again. Very slight, and on the second time the CEL came on. Just drove on down to AutoZone.
No 0401, or 0420 codes this time but a 0320 code. Reset the pcm and have driven it around for another 20 miles and have gotten a couple of minor idle glitches but no CEL.
Could I have a fouled plug, or bad plug wire somewhere? Maybe bad coil?
Going to replace plugs and wires tomorrow. Needs them anyway.
