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2003 Ford Escape Repair Question


Topics covered: Sensor, Catalytic converter, Engine.
Mileage: 142,000 miles.

Asked on February 22, 2012

CEL on O2 sensor bad bank 2

Received code 1130 from mechanic. Came up catalytic exhaust performing below threshold. Saying bank 2 sensor bad. Where is this and does this mean a catalytic converter is bad or just the sensor?
Avatar Asked by bingoprincess

Answer

Replied on February 22, 2012

Fault codes never say a part is bad or needs to be replaced. They only indicate the circuit or system that needs further diagnosis. While it's true you will find the sensor in question to be defective about 50 percent of the time, there are a lot of other possible causes for codes to set.

Bank two is on the passenger side. Most systems have an upstream, (closest to the engine), and a downstream, (behind the catalytic converter) oxygen sensor on each bank. The downstream one is just for monitoring the efficiency of the converter.

The code description I have is more informative.

P1130 – Lack Of HO2S-11, Fuel Trim At Limit.

It suggests the Engine Computer is trying to correct the fuel / air mixture and doesn't have enough adjustment capability to reach the correct ratio. That suggests the oxygen sensor is not defective; it's just reporting what it sees.

Tiny Answered by caradiodoc (expert)
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