Smart ForFour Stalling: Faulty Purge Valve Fix Guide

Had a similar issue with my Smart Fortwo (2018, gas). As someone with some hands-on experience working on cars, I initially tried checking the gas cap for proper sealing, but the problem persisted. The engine light kept triggering due to the EVAP system malfunction. After scanning, it turned out the issue was clogged hoses connecting to the purge valve. The pressure sensor was giving incorrect readings due to the blockage, causing the engine management system to get confused. Took it to an independent workshop who specialized in Smart vehicles. Total repair cost was 175€, which included cleaning the system and checking the pressure sensor connections. The stalling issue disappeared completely after the fix. To help diagnose your case more accurately, could you share: Current mileage, When the problem first started, Whether the gas cap has been replaced recently, Any error codes from the engine light, If you notice any fuel smell The EVAP system issues can have multiple causes, so these details would help narrow down the exact problem.

Last service was done at 147293 KM about 2 weeks ago. Thanks for sharing your experience. The symptoms match exactly what I am experiencing. I did notice a faint fuel smell recently. Getting error code P0456 from the check engine light, pointing to a small EVAP leak. After reading about similar cases, seems the pressure sensor and purge valve issues are pretty common in these models. Will get it properly diagnosed, but your repair costs give me a good reference point. Hoping its just clogged hoses like in your case rather than needing a full fuel tank or EVAP system replacement. Just wondering if the cleaning fixed the issue permanently or if you had to deal with it again later?

Thanks for the follow-up. Since fixing my Smart Fortwo, the EVAP system has been working perfectly for over 8 months now. The fuel smell you mentioned plus the P0456 code strongly suggests a similar issue to what I experienced. The cleaning of the hoses proved to be a lasting solution, though I did learn some preventive maintenance tips from the repair shop: Regular inspection of the gas cap seal, Keeping the fuel tank above 1/4 full when possible, Avoiding overfilling at the pump, Getting the pressure sensor connections checked during routine service One thing to note about our Smart models, the automotive repair shop mentioned these EVAP system issues often start showing up around 140-150k km, which matches your mileage. The hose cleaning resolved both the stalling and the check engine light warnings completely. The 175€ I paid included a thorough system diagnosis and cleaning. If your pressure sensor or fuel tank components need replacement, costs might be higher, but based on the error code and symptoms, it sounds like you might just need the same cleaning service I had done.

Thanks for all the detailed feedback and tips. The error code and symptoms being so similar is reassuring. Given my mileage is right in that problematic range you mentioned, I will schedule a visit to get the emission system checked and cleaned. The check engine light and stalling are really starting to worry me, especially with that fuel smell. Based on your experience with the pressure sensor and hose cleaning, I will have them focus on those areas first before looking at more expensive fuel tank component replacements. Really appreciate the maintenance tips too. I have been running the tank pretty low lately, so will definitely keep it above 1/4 full from now on. Will report back after the repair to share if the cleaning fixed my issues as well. Fingers crossed its just clogged hoses causing the pressure sensor to misread like in your case, and not something more serious with the EVAP system. The 175€ repair cost reference helps a lot with budgeting. At least now I know what to expect for a basic cleaning service and can better evaluate repair quotes from different shops.