Whats that rattle? whats that squeak?

Toyota Supra SZ
1996
2995cc
76k
I have both cats in and a nurspec catback exhaust.When I start moving off in 1st everything is fine but if I start moving off in 2nd the car makes a very bad rattle coming from underneath (sounds like the middle) I thought this might be flywheel to start with but the rattle is still there if I push the clutch up and down while moving. I think I located this to the 2nd cat. Also recently the car is making a squeaking noise a bit like two pieces of metal grinding together very fast at a high pitch - I think this is coming from near the 1st cat. This only seems to happen once the car has warmed up and I go over very rough/bumpy roads. This could be the bracket holding the 1st cat onto the gear box.Is my exhaust on its way out (the cats)? They have never been replaced so im guessing the internals are breaking up and making these noises... I took the heat shield off the 2nd cat but the rattle is still there. Sound clip:
here

The first one id agree wi you on the cat cousin had a car where cat broke n it made an awefull noise from what i remember it was similar to thatthe second sounds like a loose bolt/screw/washer somewhere possibly where u said have you had a look? or cant you get to it

Phil Holmes
Philholmes87@hotmail.co.uk
1998 BMW E36 318IS - RED

havent had chance but will look tomorrow. I probably need to cut the bolts off to see if there are loose parts in the cat as they are 11 years old - bolts needed to be melted off when i put the cat back exhaust on

id check any other heat shields as thats what it sounds like to me buddy

Congrats to phil this is a gr8 idea for a new sub forum thingy-ma-bobas for the bad rattle what only happens in second. that makes sense. i assume its trying to cut out as ur engine aint producing enough torque to pull off cleanly so your engine will be under load and will vibrate causing the rattle through the exhaust mtgs . if say you tried to pull away at 20mph in 4th or 5th gear you would experience the same rattles (at least i assume ) i very much doubt its anything with the flywheel.maybe if you try bending the mountings on the back box or on the cats if theyre 11yrs old they will of lost some of their rigidity i had a similar thing on the birds car rattling away just a quick bend with the mole grips and it straightened itself out. johny

After sticking my head out the window I have a good idea its the exhaust. I doubt the flywheel could make a rattling noise while doing 50 so must be the exhaust!! :evil: Recommendations to get these rusty bolts off to find out? :cry:

either cut the clamp and buy a new one??? thats what i had to do on my old 205.other than that eat some spinach use some wd40 and a big tourque wrench lol

Cheers for the help guys. Well tonight I was under the car removing an old heat shield from the stock exhaust days (putting her on a diet) and noticed the fuel tank protector (like a big metal cover over the tank) has holes in the bottom like vents well guess what was sticking out of each vent?!... bloody stones pebbles and dirt!!! I just watched my vid again and I can just picture them rattling about on low revs under load. Stones and metal = arrrgh :x Time to take the cover off and get these O-U-T! But.... this may not be the problem solver :cry:

i reckon it will be its sounds just like a heat sheild rattle as i thing womble says.

thy rattle be no more