P0171 on Your 2021 Jeep Gladiator
A P0171 code on your 2021 Jeep Gladiator means the engine is running lean on Bank 1. The Gladiator uses the 3.6-liter Pentastar V6 producing 285 horsepower. Bank 1 on this V6 is the rear bank near the firewall.
Like the Wrangler, the Gladiator is built for off-road use, and the engine is exposed to harsher conditions than typical vehicles. The ECU stores P0171 when Bank 1 fuel trims can't compensate for the lean air-fuel ratio.
Symptoms
- Check engine light on
- Rough idle
- Hesitation during acceleration
- Reduced power for hauling and off-road
- Lower fuel economy
- Hissing or rattling from the engine
Common Causes
- Vacuum Leaks - Off-road vibration and exposure to dirt and moisture can loosen connections and crack hoses faster than normal driving conditions.
- MAF Sensor Contamination - Dust from off-road and work-site environments heavily contaminates the MAF sensor.
- Exhaust Manifold Leak - The Pentastar V6 can develop exhaust manifold bolt issues, creating leaks near the Bank 1 O2 sensor.
- Fuel System Issues - Dirty injectors or a weak fuel pump.
Diagnosis
- Full code scan - Check for P0174 and misfire codes.
- Bank fuel trim comparison
- Smoke test - Find vacuum leaks.
- MAF and exhaust inspection
- Fuel pressure test
Repair Costs
- Vacuum hose repair - $75 to $275
- MAF sensor replacement - $155 to $340
- Exhaust manifold repair - $300 to $700
- Fuel pump replacement - $500 to $900
Diagnostic fee: $110 to $170.
Can You Keep Driving?
Short on-road trips are OK. Do not tow or go off-road with P0171 active. V6 catalytic converters on the Gladiator cost $900-$1,800. Address the lean code promptly.
Prevention Tips
- Replace air filter more often if you go off-road or use dusty job sites
- Inspect vacuum hoses and connections after off-road trips
- Follow Jeep's maintenance schedule
- Check exhaust manifold bolts periodically
- Use quality gasoline