Please respond to senior granny in terms she can understand. Thank you.

Question

Note: I am not mechanically inclined.

Purchased a 2001 Taurus SES from family friend who advised that car needed rear sway bar connections. Took car to mechanic. Seller was correct. Seller also stated that car needed work on "tail pipe" or replacement of same. Not looked at by mechanic.

Filled tank with regular gas after purchase. Drove car for 4 days with no problem other than stabilizer ends and today, engine icon lit up and stayed on. Car came up with P0156 sensor code. Heated Oxygen sensor bank sensor 2. Was told that I need a new 02 sensor but am wondering if seller's comment about muffler/tail pipe, problem could have anything to do with malfunction of 02 sensor (2).

Have done some web study and note that many mechanics state that the 02 sensor usually is not the real problem and purchasing a new one is like throwing money away.

Any advise as to how to proceed before I pour more money into this car?

Thanks for your time.

Answer 1

P0156 Oxygen sensor circuit malfunction Bank 2 sensor 2

This is the catalytic monitor, This can be a possible catlytic convertor being non operational. The catalytic convertor is a mechanical device , in order for it work and control emmission, is for it to switch from lean to rich, P0156 mean the catalytic is not doing this, Or the 02 sensor that monitor the function of the catalytic  cannot detect, and it is not doing its job. Anything that happens after the catalytic will not set this code, even if the muffler fell off this will not set this code , It what is before the catalytic that matters. Misfire can set this code, Ford has a misfire counter this means the misfire must reach a certain count before a misfire code can appear,Vacuum leaks can also cause this code such as a ruptured PCV hose. Catalytic convertors do fail due to mileage and use, So I am leaning toward the direction that the catalytic is faulty,In 2010 Ford motor company sued the oil company for the use of zinc , which lead to the degrade of their catalytic convertors,