Recognised this problem a few months ago, but was never really sure if it was cause for concern.

If I'm idling and tap the accelerator, you hear a short sucking/gas sound from the engine bay. It sounds as if the engine is strugglign to catch up with your acceleration command in that short time - after that time, it's normal.

It also happens if you're travelling at a steady speed and suddenly give it some gas - you hear the sound, and it feels as if the car/engine is lagging behind your command and takes a short while to compose itself before responding to your command and accelerating off.

I asked my dad (coach builder) and uncle (mechanic) and their first thought from my description of the noise/effect was turbo issues - but it's a 1.6L Petrol with no turbo to speak of. Is it an intake leak or a problem with the throttle body or something?

What's the best first place to look?!

sounds like its just the intake there is a lag with the fly by wire throttle give the hoses a once over but i dont think theres a issue

Perfectly normal , i took my old car in for exactly the same thing , they took me into the workshop and shown me other cars with the same noise , It's the intake.

When I first got my Focus I notcied this. It is perfectly normal. My mate at work has the same 1.6 engine in his, and it is exactly the same.

Oh okay, no problem.

Good to know it's normal. I take it's normal to suffer a bit of acceleration lag which coincides with the noise when you try to accelerate from a steady speed?

I'll give the hoses a check just to be sure then, but glad to know it's not a problem.

https://www.dropbox.com/s/27x2xs2le6stauk/2012-10-02%2020.30.34.mp4

Here's a video of the sound I'm talking about, just to make sure we're all on the same page. The video makes the sound slightly more pronounced than it is in real life though.

Yes thats exactly the same as mine was

Yes thats exactly the same as mine was

Fair enough. I'm happy with that then.

Anybody know what actually causes the sound then? Is it just the mechanism for the throttle actuator or something, since it's probably electronic, as Arthur said?

https://www.dropbox.com/s/27x2xs2le6stauk/2012-10-02%2020.30.34.mp4

Here's a video of the sound I'm talking about, just to make sure we're all on the same page. The video makes the sound slightly more pronounced than it is in real life though.

Hi GSM,

Do you still have the sound file? My Focus has recently started making a noise similar to that described in this thread.

Does anyone know what causes it, or how to fix it?

thanks in advance

Hi GSM,

Do you still have the sound file? My Focus has recently started making a noise similar to that described in this thread.

Does anyone know what causes it, or how to fix it?

thanks in advance

Read from the top , we explained what the noise is , i had my car months before i noticed it , it's just the engine sucking in the air.

If your noise is different then parhaps record it for us to hear.

Hi

I recently bought a 2012 ford focus 1.6 petrol (125) with 57000 miles on the clock. This has the hissing sound and also seems lack power and burn fuel quickly. Didnt really notice it on the test drive but now its becoming more obvious. Anyone had a similar issue and able to advise me on my best actions to take?