P1130

Air/Fuel Sensor Circuit Range/Performance (Bank 1 Sensor 1)

Car Fault Codes Toyota Emissions & exhaust

Can you still drive? Yes, normally

Who can fix it? DIY with some experience

Typical repair time 30 minutes – 2 hours

Typical cost SAR 100 to 1,200

What it means

This is a Toyota-specific code; the same number can mean a different fault on other makes. The upstream air/fuel (A/F) sensor is a wide-band sensor that measures the mixture precisely, and the engine computer found its signal stuck or outside the expected range as conditions changed. Common causes are an aged sensor or a mixture that is really lean or rich from an air leak or fuel problem.

Models covered: Toyota models with air/fuel ratio (A/F) sensors, mainly model years around 1998–2004 (e.g. Camry, Corolla, RAV4, Highlander, Sienna, Tacoma, Tundra); later models use generic codes (P2195–P2198, P0031/P0032).

Symptoms4

Check engine light on.
Higher fuel consumption.
Slight rough idle or occasional hesitation.
There may be no noticeable symptoms.

Possible causes6

Aged or contaminated air/fuel ratio sensor.
Exhaust leak ahead of the sensor letting in outside air.
Vacuum leak or a faulty MAF sensor making the mixture truly off.
Incorrect fuel pressure or leaking injectors.
Heat-damaged sensor wiring or connector.
Faulty engine computer (rare).

How to diagnose5

Read fuel trims and the A/F sensor value with a scan tool; on Toyota A/F sensors the reading rises when lean and drops when rich, and the display scale varies between tools.
Snap the throttle and release it; the reading should change clearly.
Check for exhaust leaks ahead of the sensor and inspect vacuum hoses.
Measure fuel pressure and clean or test the MAF sensor if trims are high.
Inspect the sensor wiring and connector, and compare voltages with the Toyota specification.

How to fix5

Repair any exhaust or vacuum leak.
Clean the MAF sensor or fix a fuel pressure problem if that is the cause.
Repair damaged wiring or the connector.
Replace the A/F sensor with a part that matches the Toyota specification, since it differs from a regular oxygen sensor.
Clear the codes and drive until the sensor monitor completes.

Repair cost

0–500

500–2,000

2,000–5,000

5,000+

In Saudi riyals; the highlighted part is the expected range for this fault.

A small leak or wiring repair is cheap; a genuine replacement A/F sensor sits at the top of the range.

Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026

Frequently asked questions

Can a regular oxygen sensor replace the A/F sensor?

No. Toyota's A/F sensor is a wide-band sensor with a different operating principle and connector, so use the part that matches the vehicle.

Why does my scan tool show an odd A/F reading?

Some generic scan tools display the A/F sensor on a different scale than the dealer tool. Compare with the Toyota specification and watch whether the value moves as the mixture changes.

Was this explanation helpful?

Tap the stars to rate; you can change it later.

This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

Report a mistake

Spotted something inaccurate? Tell us and we will review and correct it.