Bruce_M

Thank you for your response; no, I have not checked compression as compression is unrelated to the lack of spark delivery to 2 of the 3 cylinders on one bank. A problematic ECU is a prime candidate for the source of no spark. I have both shop repair manuals for this vehicle and trying to trace down the wiring to find a good ohm/voltage test for the spark source for just 2 cylinders is challenging, to say the least...meaning I haven't found it yet. I am hoping to find some type of test that will validate the actual problem before I start replacing parts just to be replacing parts. Thank you for your response.

I am having spark problems with my 2000 Lexus ES300 that has 119,000 miles on it. Cylinders #2 and #4 are not receiving any spark, which resulted in the catalytic converter for #2, #4, #6 completely burning and melting away with the melted chunks plugging up the aft-most catalytic converter. The only codes shown are P0300 (multiple misfire), P0301 (#1 misfire), P0302 (#2 misfire), P0304 (#4 misfire). I replaced all 3 catalytic converters, replaced all spark plug, all coils, both cam position sensors test in the middle of the allowed ohms. Have moved swapped coils between #2 and #6, and then #4 with #6; no matter what coil/cylinder position, rpm only drops when #6 coil disconnected, and no rpm difference when #2 and/or #4 disconnected. Definite rpm drop when #1 coil is disconnected. Unfortunately, the catalytic converter for #2, #4, #6 glows orange after only about 60 seconds of idling. Any ideas will be very appreciated. Thank you.