[ccstac]

I am having trouble with my 98 model 88. I started missing and check engine light flashing. Checked the code and got P300, multiple cylinder misfire. It had been about 50K since last tuneup, so gave it a new set of plugs, wires, and 3 new coil packs. Test drove it and everything seemed fine. I have about 80 mile drive to work and the next morning about 40 miles into trip it started missing again. It is missing on at least 2 cylinders. If you let it cool off for 6 or 8 hours or overnight it will run fine until it heats up good under the hood. The ecm is under the hood on this model and I had a 92 Regal do this same thing to me. I was told that it had a crack in the board and when it got hot the crack opened up and caused the misfire. Would you try a used ecm?