terrible mpg and p0171 p0174 codes
#1
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Recently my SES light came on and codes p0171 and p0174 were showing. I though it might be the because of the front 02's so i changed them. the SES light turned off and i still feel like something is wrong. it seems theres less power than normal and doesnt feel the same at WOT and is getting very bad gas mileage. any ideas? thanks