Peugeot 108 Check Engine Light Air Supply

I had a similar problem with my old Opel Corsa. The check engine light was on, and it turned out to be a defective hose connection from the pump to the valve. It caused irregular air intake which triggered the sensor. I would check all the hose connections related to the air valve thoroughly. Is the engine idling rough, or have you noticed any other symptoms besides the light?

Thanks for the insight. The engine idles a little rough sometimes, but it's not consistent. Which hose connection specifically gave you trouble on your Corsa? Was it visibly cracked, or did you find it by feel?

In my case, the crack was very small and not immediately visible. I only found it by carefully feeling around the hose while the engine was running – I could feel the slight change in suction. Given your mileage, the hoses are definitely susceptible to wear. However, I would recommend taking it to a workshop. They should be able to diagnose a faulty hose much quicker, and likely have spare hoses ready.

Thanks a lot for the advice! I took it to a workshop as you suggested. It turned out that the hose connection from the pump to the air valve had a small crack, just like your issue with the Corsa! They replaced the hose and ran a diagnostic check, and the check engine light is now gone. Repair cost me 175€ Appreciate your help in pointing me in the right direction!