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o2 Codes + P0300 (random misfire)

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Old May 10, 2014 | 01:20 AM
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Default o2 Codes + P0300 (random misfire)

p0036, p0030, p0135, p0443. These are the codes I got. When i clear them they come back almost immediately. The CEL won't go on, it will if I do 2+ starts without clearing the codes. My car started to cut power, but it went away, still got the codes though. Engine is running fine, no misfires/knock.

My car: 2005 grand prix gxp 150* nitrous, Catless DP, TEP trans, Custom tuning through DiablewTune.

I installed different maps, still the same codes. I did some research on the codes but could not find anything productive

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Ok so I found out that my 02 sensor wires were pinched , and one was broken. Put a new one in and same thing, I got codes p0443 p0030 p0036 p0443. Runs real rough and very little power. I did have the tune updated for the new gearing and all that prior to this problem. Could it have shorted out something?


Fuse was blown again, put a new one in and no more codes but one. P0300 Random missfire car runs like crap sputters and does not sound right. I think it is dumping too much fuel into the car. My Fuel pressure is a few pounds lower, MPG down 3 to 10MPG, and AFR is 13.4~ when it is usually 14.7. Any thoughts?
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Old May 28, 2014 | 06:28 PM
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check your spark plugs first check the #7 cylinder then the rest of the front plugs if they look good try moving the spark plug wire around on the front and see if that helps. I had the code and the dealer replaced the # 7 cylinder spark plug. It fix the problem.
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