Diagnostic Trouble Code
P2189
System Too Lean at Idle (Bank 2) Code
Technical Description P2189
System Too Lean at Idle (Bank 2)
What Does This Mean P2189?
This diagnostic trouble code (DTC) is a generic powertrain code. It is considered generic because it applies to all makes and models of vehicles (1996-newer), although specific repair steps may be slightly different depending on the model.
This is an ambiguous code in of itself. It can be a tough code to crack without a diagnostic strategy. During the last two starts, the engine management computer has recognized a problem with the fuel mixture at an idle.
It appears that the fuel mixture is too lean (too much air and not enough fuel) at an idle.
There is a laundry list of components that could cause this scenario. For the most part the diagnostic procedure is not difficult -- just time consuming, unless it is one of the first items checked. The strategy dictates that the driveability problems are observed and noted, then start with the most commonly found problems and progress from there.
Note: This code is identical to P2187. The difference is that P2187 refers to Bank 1 (the side of the engine containing cylinder #1), and P2189 refers to Bank 2.
This is an ambiguous code in of itself. It can be a tough code to crack without a diagnostic strategy. During the last two starts, the engine management computer has recognized a problem with the fuel mixture at an idle.
It appears that the fuel mixture is too lean (too much air and not enough fuel) at an idle.
There is a laundry list of components that could cause this scenario. For the most part the diagnostic procedure is not difficult -- just time consuming, unless it is one of the first items checked. The strategy dictates that the driveability problems are observed and noted, then start with the most commonly found problems and progress from there.
Note: This code is identical to P2187. The difference is that P2187 refers to Bank 1 (the side of the engine containing cylinder #1), and P2189 refers to Bank 2.
Symptoms P2189
1
Vehicle has a miss at an idle
2
Hard to start, especially when hot
3
Very irregular idle
4
Additional codes to pinpoint cause of original P2189 code
5
Whistling noises
6
Lower turbo boost numbers
7
Fuel smell
Possible Causes P2189
1
Faulty O2 sensor (front)
2
Faulty gas cap seal
3
Leaky or loose oil filler cap
4
Air leaking into the intake manifold downstream from the Mass Airflow sensor due to the manifold itself, vacuum hoses off or cracked, leak MAP sensor, Leak at turbo bypass or it's stuck open, power brake booster hose, or a leak in the EVAP system hoses.
5
Faulty MAP sensor
6
EVAP canister purge valve
7
Fuel injector leak
8
Fuel pressure regulator faulty
9
Leaks in the exhaust system
10
Faulty variable camshaft timing
11
Faulty ECM (engine management computer)
12
Faulty O2 preheater (front)
13
Clogged fuel filter
14
Fuel pump wearing out and producing low pressure.
15
Faulty mass air flow sensor