Knocking from under the car

[TU-Tuning]

Its coming from the middle, basically between the two front seats, it knocks randomly but if you accelrate hard or cruise at just over 3k it knocks a lot more, and a new exhuast backbox, std VT one, has just been fitted so im guessing its the centre section on the heat sheild as its not lined up right?

Just making sure really, will get it up on the axle stands tommorow morning and sort it out. Cant think of anythin else it could be in that area, its not a mechanical knock its a clanging knock if you know what i mean. Ive already reclipped the arch liners int he front as it thought it was that but its def coming fromt he middle

[chrisni1986]

check the centre section down near the back axle as they hit there sometimes!

[TU-Tuning]

Cheers mate rep left, you reckon its the exhuast aswell then? I get freaked out by any little noises in saxos and this ones big

[Dan]

Exhaust could be knocking mate, give it a shake and see if you can hear the noise.

[davevts]

as mentioned give it a shake and look for movement, although if you can hear the noise coming from between the seats then this would be where cat connects to centre

check its all lined up, i once found exhaust clamp put on at an angle where it was constantly knocking the heat shield and underside of the car.

[Luke]

Sounds like the exhaust mate, have you checked on the brackets etc?

[TU-Tuning]

Cheers lads, not checked it all yet its going up on the axle stands tommorow to get sorted as best i can.

[TU-Tuning]

Found the problem this morning;
http://i58.photobucket.com/albums/g279/99Westcoast/P3080084.jpg

The end of the brown strut you can see, where theres a cap at the end, is banging into the heatshield/shell of the car. So I tightened up the rubber hanger by moving it to the end where there seemed to be less play in the pipe. It was fine earlier but its started to tap again.

I know its def this part as the metals all shiny on the shell where the struts been hitting it, and it in the exact place the noise is coming from, but im not sure how to sort it? Maybe a new hanger, as the old ones pretty old and saggy, anyone know how much they are?

The other options cutting the strut down, but i wanna avoid this if theres a better option as its a bit of a bodge job.

[Ste]

What about bodging a rubber bushing onto the end?

[TU-Tuning]

I thought of that, but then it would still be a knocking noise wouldnt it, just a less clangy one?

[hesslevtr]

adjust the exhaust were it conects to the other pipes

[TU-Tuning]

What every connection or just the backbox one?

[hesslevtr]

what pipe is it the middle section id adjust were it conects to cat and twist away from the side its rubbing

[TU-Tuning]

yeah its the cat to BB section. Cheers ill jack it up again tommorow and try and move it across. Its odd though, the BB is only a std VT one and i had no problems before

[Ste]

Can you take a picture of before and after for future ref kinda thing?

[davevts]

sounds like the backbox is slightly pulling the centre section more to one side mate. not really a problem.

this can be easily sorted, if you have an angle ginder just chop a little off the hanger and then with a hammer bend a lip again. or just attach a rubber mount as stated above so that it sits flush with the heatshield therefor having no movement or banging.

give me a shout if you need a hand :y: