Noise Troubleshooting

[Mr Mackey]

I’ve got: 2004 AUDM Lancer CH ES 5 speed manual.

Runs well, but I’ve come across a noise that I’ve just noticed in the last few days.
It’s almost like a motorcycle sound really, not one that’s sitting at 15000 RPM, but one that’s at 3000 RPM. Not loud, but.. there.

I’ve done some basic troubleshooting: Does the sound remain regardless of engine speed – Yes, it does not change between 2000 RPM, and Idle, and Engine off.
The sound does change with road speed – the faster I go, the louder it gets. The radio does mask the sound. With the radio off it’s hard to hear as I slow below 20-30kph.
I don’t recall anything that might have triggered it, i.e. no knocks that I thought were ‘hard’, or anything like that.
It sounds like it’s from the passenger side (so for you US folk, it’s on the left hand side – the transmission side).
I can’t see the rear engine mount as having an issue.
I tested full lock each side to prove no CV joint noise, and there was none (this was at slow speed, when the noise would be hard to hear, but I was looking for clicks).
It doesn’t change sound with gears, i.e. sound is the same in neutral and in 5th. I can’t hear it in 1st (engine noise in 1st is too loud for it). 2nd at 30 is sort of there, 3rd at 30+ is definitely there.

I’m thinking along the lines of any component that moves, and continues to move at the same speed regardless of clutch state (in / out).
Is the clutch continually spinning at the same speed as the wheels?

I’m not sure if it’s transmission related (I look to it as this would likely be moving at the same speed regardless of road speed), but gear changes make no difference (and it’s there in idle).
The tyres are fairly new just a few thousand km ago.
Transmission would have fluid, changed within 2 years, I think 18 months.

I’m yet to get it up on the ramps to look under – before I do – any pointers?

To describe the type of noise, I’d say motorcycle, but I’d also agree with card between bike spokes sound – Try this, but the sound is ‘slightly different’:

Thanks in advance, hope I’ve given plenty of info 🙂

Topic

[Lorrin Barth]

My guess would be an exhaust leak. Either that or the muffler is burning out. Check for black marks where the exhaust manifold meets the head and at any other connections.

[Mr Mackey]

Thanks for the reply, but I doubt the exhaust – the sound exists when:
– Clutch is in (therefore engine is at idle) – the sound is unchanged.
– Engine is off (therefore engine is not exhausting) – the sound is unchanged.

When I said changes with speed, I meant vehicle speed, not engine sped.

[Mr Mackey]

Just another thing, the sound sounds like the car is driving at 3000 RPM, that kind of sound, slightly different.
Any thoughts?

I tried to see if it would change side today if I turn the wheel slightly (side to side inside of the lane), and that didn’t noticeably change if that helps.

What do I test next?

[Lorrin Barth]

Let me see if I’ve got this straight:
1. It sounds like a motorcycle at 3000 rpm or like a card in bicycle spokes
2. The sound increases with road speed
3. Clutch in, clutch out makes no difference
4. I assume it only makes the noise when the vehicle is moving – otherwise something is stuck in the heater fan

I guess the next place I would go would be wheel bearings although this doesn’t seem like a noise a bearing would make. But, you never know. I’d suggest raising each wheel and checking for play or noise when spun.

[Mr Mackey]

I did the test with the wheels off the ground and have a video linked below, listen for the deceleration – carefully, you’ll hear the 4cyl decelerate, and then you’ll hear the noise I’m referring to. This was taken inside the car, left side, under the glove box.

Testing on the stands: 140kph, and the noise decreases as the car slows down.

The left sound is where I’m noticing it. When I accelerate whilst on the stands it vibrates crazy. The only noise by hand sounds like warped rotors. The left side is where I feel more drag when trying to spin the wheel. The right side spins more freely.
It’s interesting that in the video, the loudest sound you hear is actually the problem sound. At the end, the slower decelerating sound is the sound.

Link to video: http://tinypic.com/r/25529md/8

It is the sound that trails, that doesn’t decelereate when the car is still rolling, it continues and then as the car slows, the sound does.
I hope my previous description matches the video sound – if not, please let me know.

I also tried testing for play by grabbing the wheel spokes at 12 and 6 and testing for any movement, none found.

Hopefully the video gives some insight..

[EricTheCarGuy]

That’s a tough one. You did say you could hear the noise with the engine off? If that’s the case, then I would check the cooling fan operation. They’re the only things I can think of that might be active with the engine off that could make noise. More info in diagnosing noises here.

http://www.ericthecarguy.com/faq/diagnosing-noises-in-your-car

Good luck and keep us posted.

[Mr Mackey]

I’m fairly sure this is a match to the noise video I posted.

[Mr Mackey]

And so I tested it with just one wheel off the ground each side, with right side up, the noise isn’t there.
With left side up, the noise is there.. thus the left side bearing must be the problem – unless someone can suggest otherwise?

If it looks like, smells like, sounds like.. it must be?

[Lorrin Barth]

Well, sounds like you are after it alright. Are you sure nothing, like a rock, got stuck in the brake rotor.

[Mr Mackey]

I took the rotor off and the noise was still there.

Now I need a easy DIY way of removing and installing a bearing.. with no press. Any thoughts?

[Lorrin Barth]

On some Mitsubishi vehicles you buy the hub, not the bearing. Check with the dealer.

[Daniel]

If the sound corresponds to vehicle speed, my guess would be a wheel bearing. And if it is making that much noise don’t fool around with further diagnosis or trying to fix it yourself. Get that thing to a mechanic immediately. The bearing holds your wheel on so you have a potentially deadly situation.

[Mr Mackey]

After a long day trying to get the bearing off – I got most of it apart and the inside of the bearing destroyed itself as I was getting the hub off.. Inner race stuck to the hub, and the guts of it fell out as I was trying to hit the outer race off.

Now I’m left with the knuckle with an outer race I can’t get out (don’t have a press).
I got the inner race off the hub using an angle grinder and some careful activity with the screw driver (just as in the video by ETCG), I even managed to avoid knicking the hub :).

Anyway, I’m stuck witth that outer race, I’ve tried a peice of pipe across the race, and hitting that with a hammer – the pipe 3/8 thick – bent to a near flat shape as I kept hitting it – I wasn’t trying to be nice.

Then I tried the use a bolt and some timber to force it out – but alas, the bolts ended up stripping their threads.

I need some DIY way of pressing out that race.
Worst still, I thought I’d check if the part would fit. Damned too big, so even if I could get the race out – I’d be stuck without the right bearing.

Edit: Oh forgot to add, we don’t necessarily know it was the bearing yet.

[Daniel]

If it feel apart like that than its a safe bet that the noise was the bearing. You need a press. This is why I suggested reading it to a mechanic. Not only do you need to, gently, press out the old race, but you need to gently press in the new one. Beating them in and out can cause metal fatigue in the hub assembly. I recommend taking those parts to a machine shop or mechanic to see if they can use their press on it.

[Mr Mackey]

All sorted, took it to a shop for them to sort the removal. It had burn marks on the outer race, so it wasn’t coming out easily.

The new one is in, all back together, noise be gone..

I recommend the best approach to this job for a DIY: Take the knuckle off whole, go to a good mech, and ask them to sort the bearing out (buy the bearing yourself first), and then put the knuckle back on. Good ones don’t seem to charge a lot, and it makes the job much easier. Much easier. Muchhh easier.

[Author]

Replies