1999 Mazda B3000 Q&A

1999 Mazda B3000 Question: Check Engine light on,p0306 code

I have a misfire on #6 code.Engine has slight miss at idle only,new plugs,wires,coilpack-thats the cheap stuff...Truck has 208k miles,but runs great.Trying to get state inspection to get Tags on it.Read here about it could be ECM?Any healp would be a Blessing-Thanks. -
Answer 1
I would start by doing a compression test and leak down test. I would suspect you may have a #6 valve seat problem. Just a hunch based on the repairs you have already done, the track record of the 3.0L V6 in that vehicle, and your super high mileage. Do the compression test to rule out base engine / cylinder head before dropping any more cash on it. -
Comment 1
Good call, I got a #4 misfire and turned out to be exhaust valve, (recessed seat). She began misfiring at 210,000mi. Found rebuilt heads with tungsen carbide exhaust seats on eBay motors. -
Comment 2
Thanks for the input guys,i just found out last week the truck is an E-85 ethonal burning setup.Have run a couple tanks of corn syrup with no change-except cold startup is much takes a lot more effort.Also a fellow mazda b3000 owner heard the critter cage chirping under the hoodand went on about the shaft where the distributor used to be causing my noise,and said it would cause engine codes from worn bearing-timing sensor issues,anyone heard of this? -
Comment 3
Yes, that would be a worn synchronizer. Kind of like a distributor. -
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