chris_barry

Put your hand or just a finger on the turbo when the rattle is happening and feel if the housing itself is vibrating. You may find its just a harmonic vibration of the whole turbo/exhaust assembly at certain RPM. You may need a cross brace of sorts to stabilise it.

The noise may be the housing rattling the turbine rather than the bearings rattling by themselves. A case of the tail wagging the dog.

If the rattle happens at a particular engine rpm rather than turbine rpm I think this could be your problem.

Chris.

Venomous S

Yeah, with mine I got a fitting that the hole is about the size of a pinhead.

koji187

I don't see how the housing would be vibrating because I bolted the compressor housing pretty tight. I checked everything and still don't know what to do...whether to keep trying to change things or to just take it off and send it to garrett for them to check it out. Any more suggestions?

chris_barry

The housing is bolted to the motor which vibrates due to internal harmonics inherent in a 4 cylinder motor. Your whole turbo/header/downpipe assembly may be hitting a harmonic vibration at certain rpm.

Why dont you put your finger on the housing like I suggested and see what you find out. If you dont notice the housing vibrating at the same engine rpm as the turbo noise then its more likely coming from inside the turbo. The suggestions people give you on this forum are all part of the psychic problem diagnosis where we only have what you describe to go by.

Accessories that are bolted to the side of a motor are vibrated by the motor. If the mass/distance/material of the accessory happen to right it can have a natural harmonic at certain rpm. I've seen alternators and throttle postions sensors that self destruct their internals at certain engine rpm. changing their location or adding a brace can make the difference.

koji187

I disconnected the downpipe and IC piping from the turbo to eliminate some possibilities of rattling. I turned the car on and rev'ed it to about 2500 rpm and the compressor housing was rattling the most. I checked everywhere around the turbo to see if it was rattling also. The part that was rattling the most was the compressor housing. As you can see from the video the compressor housing is literally jumping up and down. It is vibrating so much that after awhile my finger starts to get numb from just touching it.

Scorpion

Actaully the high pitched whine is from the compressor wheel scraping on the housing. Pull the housing off and look at the wheel, all edges should be sharp and have the same coloring as the rest of the wheel (dull aluminum look). If the edges look shiney compaired to the rest of the wheel then they are rubbing on the housing.