Matrix Stalling Idle

Greetings. The symptoms you describe indeed point to a potential issue within the tank ventilation system. The stalling at idle, combined with the check engine light, suggests an imbalance in the air-fuel mixture, possibly caused by incorrect pressure regulation within the fuel tank. Have you noticed any unusual hissing sounds when opening the gas cap, or any strong fuel odors?

Hey! Thanks for the quick reply! No hissing or fuel smells that I've noticed, but the problem is intermittent, so maybe I just missed it. If it IS the tank ventilation valve, is there any way to test it without special tools? I'm trying to avoid an expensive trip to the shop if I can help it!

While a visual inspection for cracked or disconnected hoses is advisable, a definitive diagnosis of the tank ventilation valve typically requires specialized equipment to measure pressure and flow. Given the potential impact on emissions and engine performance, I recommend a professional assessment to accurately pinpoint the fault and ensure proper repair. Replacing parts without confirming the root cause can be a costly and ineffective approach.

Took your advice and bit the bullet, went to the shop. Turns out you were spot on! Clogged hoses to the tank ventilation valve. New hoses and valve, cost me 175€ and now she's running smooth as butter. Thanks for the help!