P2191

System Too Lean at Higher Load (Bank 1)

Car Fault Codes Fuel & air

Can you still drive? With care, short trips only

Who can fix it? Needs a workshop

Typical repair time 30 minutes – 3 hours

Typical cost SAR 100 to 1,800

What it means

The engine computer has found that bank 1 runs lean when the engine is under high load, such as hard acceleration or climbing hills, and the fuel trim has reached its limit. This usually means the fuel system cannot supply enough fuel at high demand; the exact monitoring method can vary between manufacturers.

Symptoms4

Check engine light on.
Weakness or hesitation under hard acceleration or on hills.
Stumbling or misfire under load.
Nearly normal behavior at idle and during gentle driving.

Possible causes6

Weak fuel pump that cannot hold pressure at high demand.
Clogged fuel filter or pump strainer.
Faulty fuel pressure regulator.
Dirty mass airflow (MAF) sensor under-reading at high airflow.
Dirty or partly clogged injectors.
Leak in the boost air path on turbocharged engines.

How to diagnose5

Watch fuel trims during hard acceleration; trims that rise only with load point to a fuel shortage.
Measure fuel pressure under high load and compare it with the manufacturer specification, since a reading at idle may look normal.
Compare the MAF reading at high RPM with the expected value for the engine size.
Inspect the boost hoses and joints on turbocharged engines.
Check the service information for your vehicle to see its exact conditions for setting the code.

How to fix5

Clean or replace the MAF sensor if it under-reads.
Replace the fuel filter if it is serviceable.
Repair any leak in the boost hoses.
Replace the fuel pump or regulator based on the pressure test under load, and clean or replace the injectors if needed.
Clear the codes, road test under load and confirm the code does not return.

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.

The cost is low for a MAF cleaning or filter change, and rises when a new fuel pump is needed.

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

Why does the fault appear only under high load?

Because a weak pump or clogged filter may keep up during gentle driving but cannot supply enough fuel when demand rises.

Can I drive with this code?

Carefully, avoiding hard acceleration, because a lean mixture under load raises combustion temperatures and can harm the engine over time.

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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.

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