Rattle - Exhaust? Ping?

[SeanMc]

[YOUTUBE]gR2CfSt2NIM[/YOUTUBE]
At around 2 seconds you'll hear it.

Seems to only happen at low RPM. Car hasn't lost any power, or so I can tell. 70k on the rebuilt motor.

 

[SHOred]

Keep it tached up all the time and you will not hear it.

Henry

 

[geomarathoner]

Hard to tell....the squealing tires add to the difficulty.....but it might be that when the engine moves on the mounts at lower rpm, something in the exhaust piping is vibrating against the rest of the car. I had a similar sound which turned out to be the front exhaust manifold just barely touching the subframe at certain rpm/open throttle. FWIW

 

[SeanMc]

Hard to tell....the squealing tires add to the difficulty.....but it might be that when the engine moves on the mounts at lower rpm, something in the exhaust piping is vibrating against the rest of the car. I had a similar sound which turned out to be the front exhaust manifold just barely touching the subframe at certain rpm/open throttle. FWIW

Thanks!

I'll check it out this weekend.

 

[SHOtime2511]

check to see if you have some binding in the exhaust of some sort.
you have a good flex pipe right?

 

[Vnuk1]

I had a similar problem and it was the heat sheild on my cats. Just throwing that out there......

 

[NEp8ntballer]

I can't listen to the vid now but if you are still running cats they could be loose. does it sound like somebody shaking rocks in a can only more metallic? When the cat on my Jeep was on the way out it would only rattle at idle and would do it infrequently.

 

[SeanMc]

I have hollowed out cats...but it's a pretty old SHOShop ATX y-pipe. And yes, it sounds like someone shaking a coffee can with gravel in it.

Brian, I believe the flex pipe is good. Again, I'll look under the car tomorrow.

 

[Ishodu]

It could be that that baffle in the resonator is loose. Hop under there and bang things around see if you can make the noise with the car off.

 

[SeanMc]

Well, I finally was able to find what it was...it was the heat shield on the old hollowed out cats (I had new CARB cats installed yesterday). It's also in combination with leaky, and rattling exhaust flanges at the manifold, which I'll be getting fixed next week.

 

[Lupo]

See! I kept telling you that it wasn't pinging!

 

[SeanMc]

See! I kept telling you that it wasn't pinging!