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Q: Codes po171, po174, po303, po741

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I recently had my car tested and it showed the codes above. My service light is on but sturdy. I have lack of lpower and a rough idle. When I stop my car vibrates with surging on the acceleration. Prior to all of this I had spark plugs replaced and the light was still on. I was told that po352 was misfiring and had a front ignition coil replaced. I am still have problems. My car has been running great. I keep maintenance on my car but all this is new and I am a female, veteran as well as a senior citizen this is the only transportation I have and I want my car running smooth again. Please provide me with a solution I am so appreciative.

My car has 96700 miles.
My car has an automatic transmission.

First, I would like to thank you for your service. I am also a veteran. Lets look at each code and their meaning first. Code P0741 is for a problem in the torque converter clutch seal in the transmission and requires the transmission to be removed and seals or components replaced as needed after inspection.

Code P0303 is a cylinder number 3 misfire and may be the spark plug, wire, or coil causing the misfire.

Codes P0171 and P0174 are for the engine on both banks 1 and 2 running too lean. This shows you may have a vacuum leak in the intake manifold or one of the hoses to the intake manifold. The code you had before P0352 was for an ignition coil problem. It looks like you have a few different problems that will need to be looked at by a qualified mechanic. I hope this will help you decide on a repair path for the codes you have. If you still need help, have a technician from YourMechanic come to your home or office to diagnose your Check Engine Light codes and make the correct repairs.

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