Grand prix cylinder 5 misfire

hollywood_570

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Iowa
Okay, my 2008 grand prix is throwing a cylinder 5 misfire. (3800 v6) You can hear it when the car is at an idle but cant figure out for the life of me what is causing it. Changed plugs and wires. Switched coil packs, And that plate they sit on, I cant remember what it's called. Checked the fuel injectors. Did a compression test that's all good. My buddy even had one of those scope cameras and checked around said everything looked good. Replaced the rocker arm for cylinder 5 and it did nothing. I dont have any oil in the coolant, or coolant in the oil. Is there anything else I could check that would cause it? It's only throwing the cylinder 5 code. Its been sitting over the winter and I finally started it yesterday, and it smoked some down by the spark plug I believe its number 5 in the firing order. Could just be from sitting for a while, but at this point I have no clue.
 

hollywood_570

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Iowa
Yeah that's the code I'm getting, and I havent noticed any smoke from the exhaust, and I havent ripped into the intake yet. That was my next thought tho, I just wasnt sure because I wasn't getting a mix of fluids. But maybe its leaking externally? Oh also, when it first gave me problems I was driving on a 4 lane hwy going about 65-70 and the SES light came on. Then started to flash every time I would go up a hill. So I drove it home very carefully and parked it. The only time the SES light flashed was when I was at about 2000 rpm or higher.
 
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melsg5

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The LIM gasket issue does not involve any mixing of fluids.
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hollywood_570

New member
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Iowa
That will have to be what I check next. I was crossing my fingers it wasnt a head gasket. Now that I gave it another look I do see some oil on the outside of the engine by the exhaust manifold.
 
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