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.

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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