Q: Bank 1 too lean, cylinder 1 misfire.

asked by on January 19, 2017

I was driving and got a check engine light. I scanned it and got bank 1 too lean, so I decided to drive back home, on the way home my engine started shaking really bad and I figured it was a misfire, upon scanning the code again I got, P0171 and P0301, System too Lean (bank 1) and Cylinder 1 misfire detected. I have not started the car back up since then. Total I would say I drove less than 4 miles once it started to misfire. I checked the timing belt and cam gears to make sure they lined up since my timing belt was recently replaced. I cranked the engine by hand a few times and everything lined up after 4 full rotations of the crank shaft. The spark plugs are all new.

My car has 198000 miles.
My car has an automatic transmission.

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Hi there. There are several possible sources that trigger these two codes including a faulty fuel pressure regulator, weak fuel pump, clogged fuel filter, faulty powertrain control module, vacuum leak, faulty injector(s), faulty oxygen sensor(s) and a faulty mass air flow sensor. You might to have a professional mechanic complete an engine is running rough inspection at your location to pinpoint the source of this issue.

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