Hey guys. I started my car up the other day and I can hear a kind of metallic rattle coming from underneath the car. (Roughly near the shifter) It will make the noise when I first start the car on cold start but then stop. Only to reappear while driving slowly of when I back off the throttle. So not during acceleration Best way to describe it it would be a stone rolling around in a metal pipe.
Lot of guessing is required here: Assuming you have a manual - it sounds like the thrust bearing They often have noises that disappear after warming up and can also make noise on acceleration or deceleration How long since the clutch was replaced - the older the clutch the more likely.
Yeah it's a manual mate. Um I've done 60k since I bought the car and haven't replaced the clutch. When I'm driving slowly it kind of sounds like a grinding (but not like gears grinding) but it doesn't get worse the faster I go. If anything it sounds better. At first I thought it may have been a loose bolt from the shifter rubbing on the drive shaft. But that wouldn't make a noise while warming up and would get worse while driving faster
Thrust bearings can sound worse at higher revs or lower revs - they can be funny like that. It should have some slight residual noise that should be able to be heard whilst idling if it is indeed the thrust bearing on its way out. Are you able to get under the car safely whilst its idling to check for any slight noise from the thrust bearing location (have someone keep their foot on the brake etc.) No guarantees but given you haven't replaced the clutch and the fact the noise comes from under the shifter, its worth checking out JC :zlove:
Check to make sure all the bolts on the exhaust are done up and don't rattle. Could possibly be some of your catalytic converter broken off inside your exhaust and at certain sound frequencies you can hear it.
Heat shield. Check its A) attached properly and not cracked and B) rock hasnt got caught up under there on it. Not at all uncommon. Thrust bearing noises are pretty easy to pickup on. The have a whirling noise about them. If its come to the point its rattling, you would have known about it long before now. Its either the tin heat shield right under your bum, exhaust or if oem exhaust system, the heat shields over the engine pipes.
Check the rubber mounting bush that supports the gear lever(under the metal plate that bolts to the gearbox tunnel). These rubber mounts often split and sag(allowing a lot of movement in the bottom end of the Gear Lever, and some amount of noise/rattling/vibrating).
Haven't heard of megaflow but can sort you out with ADR compliant high flows here http://www.rgsperformance.com/product/magnaflow-stainless-steel-catalytic-converter/