Strange Very Loud Growling Noise Under Car

[Jon Read]

Today when I was out all of a sudden my car went from a purr to a boy racer style GROWL, really deep, except when I am in low gear and accelerating as then it is a loud eeeeeeeeeeeeeeer sort of noise that is deafening. When driving around 30 to 40mph the noise is unbearable and so loud. Then all of a sudden I think it is okay and back to normal, only to kick back in when accelerating more. When the car is just ticking over without any movement it is still louder than normal (although not as loud as when moving) and when I turn the engine off there is a final deep rumble growl (no shaking though).

There is no difference to pull that I can tell, and so it doesn't sound like the plugs. To a total novice I would say to me it sounds like the silencer has gone on the exhaust, but I have no experience to back that up.The sound seems to be coming from under the car around the front under the passenger and drivers seat, more so the passenger though. The exhaust doesn't seem to be hitting the ground and I can't notice any smells, the temp is fine. The car doesn't stall or drag. Just a loud noise that can go from almost normal to very loud, and then back again, depending on if I am accelerating and what gear (but it does happen in all gears). Seems louder in lower gear but that may be because I am stopping and starting more, same with a hill or incline (but no loss of power like I had with my plugs once).

So any experts out there have a guess ? Sorry I can't make the sound more realistic, but just imagine a slight boy racer style growl when ticking over and then a high eeeeeeear style noise when moving.

Thanks all.

[btmaldon]

It is probably the metal o-ring/seal where the exhaust meets the manifold. The join is designed to move with the engine when you accelerate, but the metal ring wears out after a time.

Its pretty easy to fix and if I remember correctly you can buy it as a kit from Fords. The kit includes new bolts, nuts, springs and the o-ring. The difficult bit is getting the old bolts off as they will be well rusted up.

Alternatively get an exhaust specialist to do it for you.

[fishpond 47]

It is probably the metal o-ring/seal where the exhaust meets the manifold. The join is designed to move with the engine when you accelerate, but the metal ring wears out after a time.

Its pretty easy to fix and if I remember correctly you can buy it as a kit from Fords. The kit includes new bolts, nuts, springs and the o-ring. The difficult bit is getting the old bolts off as they will be well rusted up.

Alternatively get an exhaust specialist to do it for you.

either that or he's run over a big dog lol, 'Loud Growling Noise'

[Jon Read]

Cheers Btmaldon, I will let you know what they say when I take it in to be looked at next week. So it is unlikely to be an exhaust issue then ? Let's hope.

Well, let's hope it wasn't a dog, although that would probably be cheaper :) I guess growl is all I could think of calling it, it is just a deep noise like you get on some sports cars, until I put it under a lot of pressure then it becomes a higher pitched motorbike style sound.