Service engine light on with a code of 173 on an 01 montero

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MITSUBISHI MONTERO SPORT SERVICE REPAIR MANUAL 1999 2000 2001 2002 DOWNLOAD

Error Code: P0154
Description:
Heated Oxygen Sensor (HO2S) 1 , Bank 2 - No Activity Detected
Problem areas:
- Wiring.
- Open circuit in signal wire, between Heated Oxygen sensor 1, Bank 2 and ECM. (Must check and confirm)
- Heated oxygen sensor (HO2S).
- Engine control module (ECM).

I have a 2001 Mitsubishi Montero sport, the check engine light is on, it's at 112000 miles, flawless car as far as I know, ran a diagnostics and got code P0400, what do you think it could be? I don't feel anything except it shakes a tad during idle and idles anywhere from 500k to 800k rpm. If you have any idea please let me know.

As far as the engine service light, I'd go to Autozone and have them read the engine codes. They'll do this for free at most autozone parts places. The codes will indicate what's wrong and you can then decide if you really need to fix it. As far as the leak, it all depends what is leaking and how quickly it leaks. Leaking a little engine or trans fluid is not a big deal. Leaking any brake fluid is always a big deal.

need to have system checked to get a trouble code

There could be a hundred causes for a check engine light. First step is to hook up a computer scan tool and see what codes the computer has. The next step depends on the codes.

most salvo auto parts stores will test your codes for free they can only offer parts not service. but its the only company that does it for free

P0173 Fuel Trim Malfunction Bank #2

The engine is probably making a knocking sound because the oil needs to be changed or replaced. The check engine light is indicating that you will need regular dealership servicing soon, however you can still drive the vehicle but depending on mileage it will determine what services are required.

does it run differently?...have codes checked ...free at most good auto parts or trans shops now.... go from there