Mokka Air Intake Leak

Hello! I have a Vauxhall Mokka too. I had similar symptoms a while back. The hissing sound, like air escaping, is a good clue. Check your air intake hose, especially the section between the air filter and the throttle body. It's like a balloon with a tiny pinhole; the engine is trying to suck in more air than it should, bypassing the air filter. Could be a cracked or loose vacuum hose as well. Does it almost feel like your engine misfires?

Thank you for your reply. You mentioned checking the air intake hose between the air filter and throttle body. Could you provide more detail on where exactly to look for potential leaks or cracks? I am not very experienced.

Certainly. Trace the large hose that connects directly to your air filter box. Follow it to where it connects to the engine's throttle body – it's usually a black plastic piece. Feel along the hose for any cracks or splits. Even a small one can cause a leak. If you’re not comfortable doing it yourself, I'd suggest taking it to a workshop. They’ll pressure test the system to find the leak. In my case, it was a split in the hose, causing all sorts of problems.

I appreciate the detailed explanation and the suggestion to get it professionally checked. I took your advice and brought my Mokka to a local mechanic. Turns out it was indeed an intake hose leaking. The repair was around 100€. Thank you for pointing me in the right direction!