2009 Impala SS P0306 Code - Stumped
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2009 Impala SS P0306 Code - Stumped I use the SS to do Uber sometimes because it is the coolest car on the planet for that! However, now I'm having troubles with her ... need your expert help!
Was driving along with passengers and car suddenly starts to run really rough ... CEL Flashing, traction control flashing, service traction control and service stabilitrak comes across the DIC. I was like holy hell what just happened?
Nursed the car home after dropping off my passengers. Hooked up the Torque app with my code reader and it says P0306 Cylinder 6 misfire detected.
I pulled the spark plug out of number 6 and number 8. See picture. Plug 6 was fouled, plug 8 looked pretty good. Thought I had my smoking gun.
I changed all 8 plugs, 8 wires and number 6 coil. Started the car up and same problem was still there. Couldn't believe it. I replaced number 6 injector with an OEM AC-Delco unit. Still did not fix it.
Now I am rather stumped ... I hear a vacuum leak when the traction control light comes on and it fades away when the light goes out. With the new parts it is acting this way intermittently but still feels a little rough and missing some of its 303 horses. I drove it about 10 miles and when I parked it and got out it smelled like it was burning extremely lean. I can take it up the road and all lights will go out (P0306 stored historically) .... it will be normal for several minutes but then right back to everything coming on.
Has anyone seen this before? I saw a thread on the code but no real explanation to a solution. Someone please tell me what the heck is going on ! LoL! I just bought this car in December ... I do love it but aI am hating it right about now!
Thanks and looking for to your responses!
Rich
Was driving along with passengers and car suddenly starts to run really rough ... CEL Flashing, traction control flashing, service traction control and service stabilitrak comes across the DIC. I was like holy hell what just happened?
Nursed the car home after dropping off my passengers. Hooked up the Torque app with my code reader and it says P0306 Cylinder 6 misfire detected.
I pulled the spark plug out of number 6 and number 8. See picture. Plug 6 was fouled, plug 8 looked pretty good. Thought I had my smoking gun.
I changed all 8 plugs, 8 wires and number 6 coil. Started the car up and same problem was still there. Couldn't believe it. I replaced number 6 injector with an OEM AC-Delco unit. Still did not fix it.
Now I am rather stumped ... I hear a vacuum leak when the traction control light comes on and it fades away when the light goes out. With the new parts it is acting this way intermittently but still feels a little rough and missing some of its 303 horses. I drove it about 10 miles and when I parked it and got out it smelled like it was burning extremely lean. I can take it up the road and all lights will go out (P0306 stored historically) .... it will be normal for several minutes but then right back to everything coming on.
Has anyone seen this before? I saw a thread on the code but no real explanation to a solution. Someone please tell me what the heck is going on ! LoL! I just bought this car in December ... I do love it but aI am hating it right about now!
Thanks and looking for to your responses!
Rich
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Yes. I sprayed ether all around all major vacuum connections including the upper intake. I did not get an increase (or decrease) in engine idle or performance when doing this. I had a friend of mine go around with a sniffer stethoscope and he could not hear it either.
You didn't give much info on what has been done to the car or mileage but plugs 1, 4, 6 and 7 are DOD and will all be dirtier even more so if it has high mileage. I would clean the TB and MAF also(cheap and easy). Sounds like a vacuum leak to me, but could be electrical so check the battery and all grounds. Here is a post from another forum, not sure if that is your problem but worth a read. Good luck.
http://forums.trailvoy.com/showthread.php?t=82660
http://forums.trailvoy.com/showthread.php?t=82660
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Follow up I just got the car in December and not real sure of its history. Car has 119,000 miles on it now. No mods at all.
I did a compression test on cylinder 6. I unplugged the coil power leads and took #6 plug out. screwed in the compression tester and cranked it 3 revolutions. I did that 3 times and got 160 on the gauge each time.
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You didn't give much info on what has been done to the car or mileage but plugs 1, 4, 6 and 7 are DOD and will all be dirtier even more so if it has high mileage. I would clean the TB and MAF also(cheap and easy). Sounds like a vacuum leak to me, but could be electrical so check the battery and all grounds. Here is a post from another forum, not sure if that is your problem but worth a read. Good luck.
http://forums.trailvoy.com/showthread.php?t=82660
http://forums.trailvoy.com/showthread.php?t=82660
Thanks that was a good read and I will try to clean the throttle body and the MAF. I love this car and it is killing me that it is sitting there running like crap ... does not make any sense!