I think it's a resonant frequency thing. Securing the pipes to each other (adjacent to the separator) changes the vibrating length and therefore the resonant frequency. Same principle as pressing your finger on a guitar string.

On 9/20/2018 at 10:00 AM, EightiesDuntonFordie said:

WOOHOO! This fix worked on my car too!!

Thank you, thank you, thank you for posting the fix. I'm ridiculously happy about this. I really love my Fiesta, but the 'wasp in a jam jar' noise in the glovebox area was driving me mental, and taking the shine off driving the car.

BTW: I used a single tie strap, in the 'blue' location. I used a really fat one (about 1cm wide) to avoid the risk of digging into the hoses, and I placed it immediately behind the black plastic separator in order to give the hoses something to push into rather than just squeeze them together.

Happy days - thanks again!

(I'm assuming your car is left hand drive? On a right hand drive car, the two hoses are on the opposite side of the car to the pedals. Same location as per the picture but on a rhd vehicle these are on the passenger's side, so no throttle / brake components here).

Hello can you post a guide and pics how to do the fix. I don’t see the pics maybe the post is old....  I have a fiesta mk7.5 3dr titanium and I have the buzzing noise behind the glove box like you’ve all described and it’s quite literally sending me round the twist especially seeming Arnold Clark said they found nothing wrong but it’s definitely there under accelerating.    Please help I’m losing my sanity

I have a September 2021 Fiesta MHEv  ( built December 2020 ) and this too has the “wasp in the glovebox” sound.

Is anyone who contributed to this topic still active on the forum? Is there a permanent fix? 
 

If the cable tie around the heater pipes is a long term fix I’ll try to order some wide cable ties off Amazon.