# P0300, P0174 check engine codes, rough idle, smell



## BlueBeast85 (Dec 5, 2013)

Hey guys just looking for some information and help if possible. 4 months ago I replaced the o2 sensor due to the same issue and now randomly 4months later the same issue. The car is running too lean smells awful at times, idles really rough at a stop, and is getting poor gas mileage again. The first code is a random misfire, 2nd is bank2 system too lean. Any ideas? Thanks.


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## gmonde (Apr 25, 2014)

check the converter on bank 2,, chances are that the converter is clogged and the first sensor and second sensor is not getting correct info ,, telling the engine to back off on fuel ,,, pull the covert and check it ,, mine was broke and caused it to clog obvious, some times you might have to do the water test ,, gmonde


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## Cooper06 (Apr 29, 2018)

BlueBeast85 said:


> Hey guys just looking for some information and help if possible. 4 months ago I replaced the o2 sensor due to the same issue and now randomly 4months later the same issue. The car is running too lean smells awful at times, idles really rough at a stop, and is getting poor gas mileage again. The first code is a random misfire, 2nd is bank2 system too lean. Any ideas? Thanks.


My car is doing similar things what eventually fixed your car? I’ve tried everything MAF sensor o2 sensors new plugs wires etc


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