P2178

System Too Rich Off Idle Bank 1

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$17–94 (est.)

Symptoms

Increased fuel consumption
Black smoke from the exhaust pipe
Unstable engine operation under load
Power Loss
Gasoline smell from exhaust

Causes

Malfunction of the mass air flow sensor (MAF)
Leaks in the vacuum system
Dirty or faulty fuel injectors
Problems with the fuel pressure regulator
Malfunction of oxygen sensors

How to Fix

Check the MAF readings and replace if necessary
Inspect vacuum hoses for leaks
Conduct fuel injector diagnostics
Check the pressure in the fuel system
Test oxygen sensors

Related codes

P0172 P0175 P2187