Fix code P2187 P2189 on Hyundai
If you find a P2187 P2189 Hyundai trouble code, don’t start throwing parts at the problem. The two codes P2187- bank 1 system lean, and P2189- bank 1 system lean may lead you down the wrong path of thinking you’ve got a fuel delivery problem. Most DIYers start by changing the fuel filter, checking the fuel pressure, or cleaning the fuel injectors.
But these two P2187 P2189 Hyundai trouble codes can be caused by a faulty EVAP system purge valve. This valve is a common failure point. When the valve sticks open, the intake continues to suck fuel vapors from the charcoal canister. The oxygen sensor sees a rich mixture and commands a leaner mixture to compensate. These valves can also develop cracks in the vacuum hose from the charcoal canister to the valve and from the valve to the intake.
If you have a scan tool with live data, see if the fuel trims are too high. If so, pinch off the vacuum line to the canister purge valve to see if they change. If so, you’ve found your problem. If the fuel trims are low or negative, try the same trick. That’ll block off extra fuel from the canister. If that works, replace the valve.
For more information on how the EVAP system works, read this post
©, 2015 Rick Muscoplat