Was does system too lean bank 1 and bank 2 mean?

ANSWER : Yes, bank 1 and bank 2 is the same as left and right. Bank 1 is the right side of the engine and bank 2 is the left. Before purchasing and replacing the catalyst, you should have a complete diagnosis of the codes you are receiving from the engine computer. You may need to do additional repairs before the catalyst is replaced or damage to the new catalyst may happen. I recommend having a mechanic verify the computer systems are clear of any problems before you can install the new catalyst. If you would like to have the car checked, a qualified professional from YourMechanic can verify the issue and move forward with any needed repairs.

ANSWER : Hi there:

It would be best for you to review these two links; the first describes what the P0151 OBD-II Trouble Code is and what typically causes it, and second, the P0131 code and what it means.

ANSWER : Hi there. When the two codes P0171 and P0174 come up for a lean system on both banks of your engine, then either all of the fuel injectors are not working properly or your fuel pressure has dropped. Check the fuel pressure on the fuel rail and see what the pressure is at idle and when loaded. If the fuel pressure is less than 45 psi but greater than 15 psi, then the pressure regulator needs replaced. If the pressure is lower than 15 psi, but has more than 1 psi, then the fuel pump needs replaced. If you need further assistance with your emissions problem, then seek out a professional, such as one from Your Mechanic, to help you.

ANSWER : Hello. The code you have provided is not a valid automotive error code that I recognize. Based on your context I think it may be possible that there is an issue with the signal range of one of your oxygen sensors. If you’ve replaced the sensors then perhaps the issue may be with the wiring. I would carefully examine the wiring to the oxygen sensors, as well as the connector and contacts for any signs of damage, wear, or corrosion. If the sensors and wiring all check out then it may be possible that the issue is with the computer.

ANSWER : 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.

ANSWER : First, the EGR tube rusted away will cause excessive air to get into the exhaust and cause the O2 sensors to read erratic. The main reason you most likely have a mass air sensor that is not reading correctly for the altitude you are at. You should check the mass air sensor with the key on and engine off to see if the barometric sensor is reading the correct altitude. If it is reading above 10,000 ft, then replace the mass air sensor. Disconnect the battery for 10 minutes to clear fuel control then road test for problem. If you need a diagnosis, a certified technician from YourMechanic can come to your car’s location to inspect the loss of power and advise you on repair.

ANSWER : If you have codes stored in the engine computer for lean bank 1 and 2 is caused by the entire engine is running lean. This is caused by not enough fuel getting into the engine or too much unmetered air getting into the engine and the computer cannot compensate anymore to run it normal. Have the engine fuel pressure checked and also check the engine for any vacuum leaks. If further diagnosis is needed then contact a mechanic like one from YourMechanic to do more diagnostics if problem is not found.

ANSWER : If lean faults occur after the manifold was removed and reinstalled, this indicates a vacuum leak which also means that unmetered air is coming into the intake. Either a vacuum line or induction pipe is loose, or the manifold is not seated correctly. The repair needs to be double checked. If no obvious items are found, a smoke check of the induction may need to be performed to locate the source of the unmetered air leak. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the equipment and training to diagnose the error codes and help you move forward with the appropriate repairs.