Exhaust/engine rattle at startup

[skwerl]

About 3 days ago my car began making this obnoxious noise at cold startup. After 30 seconds it sounds normal and nothing else seems amiss until I start it up the next morning. I spoke with my mechanic this morning and his first thought was a cam phaser or timing chain adjuster, but he hasn't heard it in person yet. I'll be sending him this video as well but wanted to get some feedback here. The car has 28K miles, about 12K with the blower.

 

[dark steed]

Can you get a video close to the engine, not the exhaust? Unless the rattle is coming from the back, the exhaust is just covering up the real noise.


Sent from my iPhone using Tapatalk

 

[skwerl]

Sure, although I'll have to wait until later today after the car is cold again.

 

[shikwann]

Mine does the same damn thing

 

[Roush05]

Sure, although I'll have to wait until later today after the car is cold again.

If it comes from the engine, you may need lockouts.

 

[delz05]

I had a similar noise coming from my car as well. Discovered that the exhaust hanger, right under the center console, was vibrating until it warmed up. Bent the hanger into a steeper angle, noise went away. Had chased that for about two weeks before figuring it out. Noise popped up 2 days after blower install...

Good luck with the hunt...

 

[pfaut]

I get a rattling noise under my car when it's cold. I thought it might be the heat shield on the catalytic converter. I had the dealer check it but they said it was ok. Might have been warm at the time though. I'll have to check the exhaust hangers.

 

[07VistaChicago]

I had a rattle when cold twice, each time was my 02 sensor that had come loose or wasn't tightened enough.

 

[skwerl]

Didn't have time to record it today under the hood. I did check for engine codes yesterday and there are none. My mechanic wants to hook it up to his computer and watch the power balance on startup. He's full tonight so I'll drop it off tomorrow night and he will check it Thursday morning.

 

[Rene06GT]

Any after market springs? Did u make recent changes?

 

[Rasmus]

If it sounds like it's coming from the engine, it's the little O-ring on the back of the timing chain tensioner that has begun to fail causing it to leak down. Happened to me twice.

 

[EBLeon14]

I get a rattle behind the console at 1500 RPM

 

[delz05]

That console rattle could be the exhaust hanger directly under...

 

[05stroker]

That console rattle could be the exhaust hanger directly under...

That's why I did the hanger delete. Noise gone!

A buddy at my dealer told me about it, so I cut them and never looked back. Did the same thing with my 3" off road x for ARH when it came as well.

 

[EBLeon14]

Which hanger?

 

[skwerl]

Well this morning my mechanic hooked up the computer, raised the car on the lift and had himself and two others all under the car when they fired it up. As mentioned earlier, the noise only lasts about 30 seconds and then it's gone. Good news is that it's just the muffler baffle coming apart. Bad news is that I've already replaced that muffler once and I really like the Bullitt mufflers but the extra flow and pressure from the blower and not having the cats is overwhelming those mufflers (according to my mechanic). And only the right muffler gets blown out, left side is still original.

I have the left muffler from the replacement set I bought a couple months ago. I'm going to take it to my welder and have him swap the pipes and hangers so I can use the left muffler on the right side. That should buy me a few more months for cheap until I figure out a longer term solution.

Thanks for all the suggestions, guys.

 

[05stroker]

Which hanger?

the hangers on the midpipe

 

[Pardue]

Well this morning my mechanic hooked up the computer, raised the car on the lift and had himself and two others all under the car when they fired it up. As mentioned earlier, the noise only lasts about 30 seconds and then it's gone. Good news is that it's just the muffler baffle coming apart. Bad news is that I've already replaced that muffler once and I really like the Bullitt mufflers but the extra flow and pressure from the blower and not having the cats is overwhelming those mufflers (according to my mechanic). And only the right muffler gets blown out, left side is still original.

I have the left muffler from the replacement set I bought a couple months ago. I'm going to take it to my welder and have him swap the pipes and hangers so I can use the left muffler on the right side. That should buy me a few more months for cheap until I figure out a longer term solution.

Thanks for all the suggestions, guys.

I have a nice set of Bullitt mufflers I would be willing to sell. PM me if you are interested and we can work out something.

 

[delz05]

Try a set of GT500 mufflers (semi-quiet)...or a set of Stingers (mild at idle, loud at throttle, roars at WOT!) or similar.

So far so good with my M90 set up....