P2198Fuel & Air Metering

O2 Sensor Signal Stuck Rich - Bank 2 Sensor 1

P2198 means the upstream oxygen sensor on bank 2 stayed stuck reporting a rich condition when the ECM expected it to switch, so it cannot use that sensor for fuel control.

🚗 Yes, usually, but fuel trims may be off. Diagnose soon.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Failed upstream oxygen sensor$100-$350

40%

A slow or contaminated O2 sensor sticks at a rich reading.

#2Actual rich condition$100-$500

25%

Leaking injectors or high fuel pressure keep it reading rich.

#3Contaminated sensor$100-$350

20%

Oil, coolant, or silicone contamination skews the sensor rich.

#4Wiring or connector fault$50-$300

15%

A damaged sensor circuit skews the signal.

🩺 Common Symptoms

Check engine light
Poor fuel economy
Black smoke
Rough running
Failed emissions test

💰 Repair Cost: DIY vs Shop

DIY Cost

$30-$500

Shop Cost

$150-$600

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P2198

1Read O2 sensor live data for switching activity

2Check fuel trims for a true rich condition

3Inspect injectors and fuel pressure

4Replace the upstream oxygen sensor if it is not switching

❓ Frequently Asked Questions

Can I drive with a P2198 code?

Usually yes, but a rich condition wastes fuel and can foul the catalytic converter.

How much does it cost to fix P2198?

An oxygen sensor replacement typically runs $150-$600 at a shop.

What causes P2198?

Usually a failed upstream O2 sensor or a real rich condition on bank 2.

🔗 Related Codes

P2195P2196P2197P0175P0152