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Q: Miss fire cylinder #1, bank 1 sensor 2 codes

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My Jeep just started to loose power when I was getting onto the freeway the other day. Would not drive over 40 mph and sputtered and backfired a few time before shutting the motor off. Check engine light flashed and threw two codes, miss fire in cylinder #1 and bank 1 sensor 2. Could I have a bad cat, injector which is more prevalent? Checked the plug and wires they looked good and now the Jeep runs decent but can tell there something still off and it threw the code again after about 12 miles after being cleared.

My car has 136400 miles.
My car has a manual transmission.

A: Hi there. Before going after a possible cat...

Hi there. Before going after a possible catalytic converter or oxygen sensor bank(1) sensor(2), the misfire needs to be corrected. The check engine light flashing would be ECM (engine control module)/computer recognizing the misfire. The spark plug and spark plug wire appearing okay, does not necessarily mean they are okay. The fuel injector could be at fault. Resistance value tests, using an ohmmeter could help isolate the problem. Comparing the resistance value with known good cylinders would give you an idea, what you should expect to see. Proper diagnoses needs to be performed to avoid unnecessary repairs. I recommend having your vehicle’s #1 cylinder misfire be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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