Its either loose or breaking down internally.
If your Alfa Romeo 147 1.6 Tspar is experiencing a major loss in power, the problem could be the catalytic converter.
There should be no noises near your catalytic converter on your Renault Clio. If there is a noise there is most likely a part that is loose on the converter or near the converter. It may not necessarily be the converter. I would chech around the area also for other noises.
Your Mazda Protege might make rattling noises when parked because of a loose or damaged muffler or even body panels that are loose. It might also make a rattling noise because of a damaged motor mount.
A possibility may be a loose catalytic converter shield, or loose muffler hanger or clamp. Usually a noise like this is caused by something that is loose and vibrating. These issues are usually not complicated or expensive to fix. If you're talking about the engine making rattling noises, the timing may be off, or it may be running too hot. Also, make sure you're using gas with the proper octane for your car. An engine noise like this is called "detonation". Detonation can cause engine damage if left untreated long enough.
If your talking about it doing that after you have turned off the engine then yes. That's just the hot exhaust pipes and catalytic converter contracting as they cool.
yes
actually I just had this problem and believe it or not it was the driveshaft u joints. It could also be your catylac converter. Get under the truck and hit the converter with your hand. If you here some rattling noises your converter is shot. Too check your ujoints just give the driveshaft a good wiggle to see if ujoints are shot
Possible side effects include rattle noises, check engine light, different smell from exhaust, low power, low fuel economy,
bearings old tires shock observers steering wheel
a mechanic heard a rattling under my 95 and said it was a small hole in my muffler pipe and it will get bigger if i dont weld it but someone else said the pipe was loose and knocking on the clamp 50k ago, I had to remove the heat shields from the catalytic converters. Took care of it!
making noises.
making noises