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My car is misfiring, codes p0171 and p0300 come up on the code reader. It idles rough and has very little power. I have checked my exhaust , it is not plugged. When I unplug coil #2 while idling there is no change as to the engine performance so I switched the coils around with no difference when coil is unplugged on cylinder #2. I have changed the plugs, there is power to the coil, all plugs are firing and when removed plugs 2 and 3 are wet with fuel indicating I am getting fuel and fire. I have replaced the cam sensor with no change.
I am running out of ideas, if anyone has any ideas or has had the same issues please help me before I burn the darn thing.
 

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My car is misfiring, codes p0171 and p0300 come up on the code reader. It idles rough and has very little power. I have checked my exhaust , it is not plugged. When I unplug coil #2 while idling there is no change as to the engine performance so I switched the coils around with no difference when coil is unplugged on cylinder #2. I have changed the plugs, there is power to the coil, all plugs are firing and when removed plugs 2 and 3 are wet with fuel indicating I am getting fuel and fire. I have replaced the cam sensor with no change.
I am running out of ideas, if anyone has any ideas or has had the same issues please help me before I burn the darn thing.
It looks to me like it could be a bad spark plug wire on number two. Have you changed the wires yet?
 

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p0171 is a lean condition. p0300 is random misfire so no surprise there, if the ecu ¨see¨ a lean condition, it will command the ecu to send more fuel to the injectors, up to a point it will not compensate any more. you might have a vacuum leak or, worst case, a bad head gasket. check the air intake hose for air leaks, or a bad air leak at the hose for the brake booster. now, cylinders 2 and 3 are close together and they are wet. do a compression test and if those 2 cylinders are below specs, you might have a bad head gasket. if the car overheated at some point in the past, then you probably have a bad head gasket. if the car is consuming coolant or if , with the engine cold, open the radiator cap , start the engine and watch, and you see air bubbles coming out, you most likely have a bad cylinder head gasket. if you dont have a compression gauge, do a vacuum check. if vacuum gauge jumps, no steady reading or below 19 hg, you probably have a bad head gasket. if you have access to a scanner with real time data and you see your short term fuel trims at -25%, engine load at about 30% or higher, and the o2 sensor voltage(bank 1) close to .9-1 volt, i would say you have a bad head gasket. solution? remove the cylinder head and take it to a machine shop to get it overhauled/rectified. after an engine overheat a cylinder head can warp and they usually do towards the middle of the unit and there is where cylinders 2 and 3 are located. in that case, replacing the head gasket without machining the cylinder head wont fix the problem.
 

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cylinders 2 and 3 are not firing, but the coil is good, then check the wiring that go to the plug of the coil that go to cilynder 2. check that connection. if that coil is not firing because of a bad wire or electrical connection, spark plugs 2 and 3 wont fire. that might be your problem
 
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