Is it safe to drive with a P0172 code?

Severity is medium. Address P0172 sooner rather than later — driving with an active check engine light can worsen the problem or void emissions warranties.

How much does it cost to fix P0172?

Repair costs for P0172 typically range from $20 to $700 in the US, depending on the underlying cause. The most common fix is: Leaking fuel injector(s).

What are the symptoms of P0172?

Check engine light. Strong fuel smell. Black smoke from exhaust under load. Fouled spark plugs. Poor fuel economy. Rough idle.

Check Engine Code

P0172

System Too Rich (Bank 1)

Severity: medium DIY difficulty: 2/5 Typical cost: $20–$700

What P0172 means

Opposite of P0171 — long-term fuel trim has been pulled well negative because the ECM is cutting fuel to compensate for a rich condition.

Symptoms

Check engine light
Strong fuel smell
Black smoke from exhaust under load
Fouled spark plugs
Poor fuel economy
Rough idle

Likely causes (most common first)

Leaking fuel injector(s)
Failed fuel pressure regulator
Contaminated MAF sensor reading low
Restricted air filter or intake
Failed O2 sensor stuck rich
EVAP canister saturated with fuel

Can I keep driving?

Medium — drivable but fix soon

Typical repair cost

DIY fixes can start near $20 (parts only). Shop repairs for P0172 typically run up to $700 depending on the underlying cause and vehicle. Start with the most common cause — Leaking fuel injector(s) — before throwing parts at it.

Related codes

P0171 P0175

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