Stalling Buick Excelle Points to EVAP System Failure

Had similar issues with a 2019 Buick Envision. The check engine light activated after the EVAP system showed problems, and the engine would stall at idle speeds. Despite having a new purge valve, the symptoms persisted. The root cause was a defective activated charcoal filter, which restricted proper air flow in the emission control system. The old filter had become saturated and clogged, preventing normal fuel tank ventilation. This created irregular fuel pressure and affected engine performance. The repair involved replacing the entire charcoal canister assembly since the filter is integrated into the unit. Not a severe mechanical issue, but it requires proper diagnosis because symptoms can mimic other EVAP system problems. The stalling issue completely resolved after the repair. Important to note that a faulty purge valve replacement alone might not solve the problem if the charcoal filter is compromised. Would suggest getting the EVAP system fully tested to identify any potential leaks or blockages.

Thanks for sharing your experience with the charcoal canister replacement. Currently dealing with the same stalling and check engine light issues on my Buick. My purge valve replacement did not solve the problem either. Just wondering, do you remember the repair cost for the canister assembly? Also, has your fuel efficiency improved since the fix? The air flow issues have been really affecting my gas mileage lately.

Had the repair done last week actually. The leak detection test confirmed my suspicions about the fuel tank ventilation system. Total cost came to 275 for parts and labor to replace the defective activated charcoal filter, which was the root cause. Fuel economy has definitely improved since fixing the emission control system. Before the repair, the compromised air flow was causing the engine to run rich, burning more fuel than necessary. Now getting about 15% better mileage with the new filter properly handling the fuel vapors. The check engine light hasn't returned, and the stalling issue is completely resolved. The investment was worth it for both the improved performance and fuel savings. Make sure your mechanic performs a complete EVAP system diagnosis to confirm its the same issue before proceeding with repairs.

After dealing with this stalling problem for weeks, I finally got it fixed yesterday. Took it to a different shop that specializes in emission systems. The technician ran a complete EVAP system diagnostic and found that my charcoal canister was indeed clogged, just like you experienced. The repair cost me 290 Euro for everything. Been driving it since yesterday and already notice a huge difference. The engine runs smoother at idle, no more stalling, and the check engine light is finally off. Even filled up the tank today and can tell the fuel efficiency is much better already. Thanks again for pointing me in the right direction. Would have wasted more time and money on unnecessary repairs without your input about the charcoal filter. Guess that first shop missed the real problem when they replaced the purge valve. Lesson learned about finding a mechanic who really knows their way around emission control systems.