2001 Hyundai Sonata PO172

TWOANDAMILLION

MEMBER
2001 HYUNDAI

My 2001 hyundai sonata 4 cylinder has thrown a po172 code "Burning Rich bank 1." I was told by 3 different mechanics to replace the oxygen senors. I replace both. Still throwing a po172 code and the engine runs rough at idle and during take off and sudden acceleration. I replaced the spark plugs and coils as well. Everytime I take it to the dealer they say I need a tune up but I did that on my own. I am dumb founded what to do next. The car does fine when it is at a steady speed past 25 mph. What should I do next?

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

PO172 is a typical symptoms of an engine that is running rich (too much fuel, not enough air) are poor fuel economy, elevated emissions (Carbon monoxide or CO), and engine may have rough idle or surge condition.

Possible causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.

Hope this helps