This happened to me while I had my scanner plugged in. I was troubleshooting an Evap Control Valve when the MIL started flashing and I pulled the codes. Just as has been indicated I had a misfire on #5. Did tuneup this past weekend and found nothing wrong with #5, but #8 had oil soaked all around the base of the plug and the wire. Probably fouling out occasionally. These cars have crappy seals around the plug cavity on the 4V's IMHO... And sure enough the seal on #8 had broken up. Guess I'll have to do the same thing I did on #6. Carefully filled it in with RTV and let it cure good. No problems on #6 since. I had a lot of miles and years on the original wires anyway. Mine's a '96 and the wires were the originals.
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