p0306 code on mitsu endeavor 07 v6 3.8

[bigsezza]

hey everybody..I have noticed on my 07 mitsu endeavor that the idle was very rough..The check engine light came on and I got a P0306 code from an actron scanner..The code indicates a cylinder 6 misfire..I took the plug out and the tip of the plug had oil on it..i asked a mechanic and he told me that its probably a bad valve seal..Im bringing it in to get serviced over the weekend.Ive been running 5w20 full synthetic( PP, Valvo synpower) in the truck since about 45k..the truck now has 70k on it..the oil is due for a change and I dont know if i should stick with the 5w20 full syn or go with a 5w20 synthetic blend.. Any and all suggestions would be a great help since this is the place to ask a motor oil question..

I do oil changes about every 5 to 5500 miles..The truck sees mostly stop/go but gets some highway use also..I live in NYC area..thanks for the help

 

[HerrStig]

Perhaps it will turn out to be a bad plug/wire.coil problem, but for some reason Mitsu has had a lot of valve guide/seal problems over the years. See an older Chrysler minivan smoking...probably a Mitsu V6 in it.

 

[bigsezza]

I also heard that either one of those could be the issue..but wouldnt having oil on the plug indicate another issue..the truck doesnt smoke at all but im thinking if i should maybe change from a full syn to a synblend or just continue using full synthetic but maybe go to a different weight oil

 

[Brons2]

I don't think the oil used has anything to do with the problem.

 

[bigsezza]

I have read several places that these 3.8l motors are notorious for oil consumption..So i would agree with you there..Ill continue using PP and then bring it in for service and see what they tell me..thanks

 

[artificialist]

Having the cylinder heads rebuilt might solve the problem at a high expense, but if that doesn't work, the whole engine would need rebuilding.

Seems like most Mitsubishi V6 engines are problematic.