Code p0155

please note that the standing voltage of the sensor (at idle) before replacement was about .04 (bank 1 was .20) and after replacement was .72 (bank 1 was .76) so much closer.

Hi,

Checking the wiring and the connections is a perfect place to start. If that doesn't help, then we need to move to checking the circuit.

Is the engine running normally? The code indicated there could be a short, an open circuit, or even a PCM issue.

If you look below, I attached the diagnostics specific to this code. Let me know if you are comfortable performing the tests.

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below.

Realized that i had put this as a Montero and not a Montero sport. I own a 2002 Montero sport.

It runs pretty rough at idle.

Hi, Tim.

The Sport has the same procedures listed. That's fine. Have you had a chance to check the wiring? Also, by chance, do you have a live data scan tool? If you do, could you let me know the short-term fuel trims? Also, let me know if you have checked for vacuum leaks, fuel pressure, and basic system checks.

I'll watch for your reply.

Joe

hi Jacob, I did check for vacuum leaks, it is possible that one of the boosters or a vacuum line has a leak that i did not find, but i looked pretty carefully, i have screenshots of pretty much all the basic system checks, (have not checked fuel pressure yet that seems like a good one).

Tim,

If possible, check the fuel pressure. Also, if you follow the link I provided above, it will show how to find leaks that aren't visible.

Let me know what you find.

Joe