Sometimes miss fires so much at road speed or times its occasional. dealer can't figure it out. R cop & ecm.
can't locate problem.
Dealer replaced cop#1 and ecm and had the car for almost a month. only thing left is the wiring harness which is more expensive than the ecm.
Toyota has had same or similar problems with the years and sub brands.
Anonymous
Hi so no easy or quick fix time to get it to a toyota dealer.
Anonymous
Oh
The Devil
P0351 - Ignition Coil 1 Control Circuit
Maybe a bad coil. Swap them around to see if the code changes from 1st coil, to 2nd coil, to 3rd coil, then through process of elimination, replace the bad coil or leads to the coil.
CactiJoe
Most likely a mechanical problem if you can't narrow it down with the code puller. ECM (black box) might be defective, too. Could be as simple as a boogered up spark plug or a dying coil or a plug wire throwing spark to the block, through the insulation, damaged or not damaged. Have seen this happen even with new plug wires. If the simple issues are eliminated, then you might have to check the timing belt. The teeth or ribs wear on the belt and on the timing belt "gears" or pulleys under the cover and could slip one notch and throw off engine timing noticeably.
Anonymous
See an independent garage with a good reputation for diagnostic work. Do not assume anything when doing a diagnosis. Replace all the plugs. Check all power and control wiring (fuse to coil, PCM to coil) for damage, cuts, burn marks. Check the misfire data with a (expensive) scanner. It will show what cylinders are misfiring. Check each of the COP. Look for any burnt marks, cracks or wear. Check all the primary and secondary wire amperage (current ramp) with a scope on each coil to check if any of the coil is/are shorted.
https://www.youtube.com/watch?v=6kvYjYT1_mM