Exhaust Tick

[01yellercobra]

A friend of mine has a weird ticket coming through his exhaust. We could slightly hear when he had Magnaflows. But now with Carvens it's really noticeable. You can hear it through the exhaust pipe. Mostly driver side I think. At first I thought it was the tick, but you can't hear anything in the engine compartment. The car runs fine. He did pull an O2 sensor code recently, but it was there before the code popped. No stumbles, no quirks. Pulls strong. A compression check and leak down is next on the list. Just thought I'd see if anyone else might have heard of this.

Video:

 

[hotcobra03]

That's loud,,and fast,

Hopefully a loose plug .

I had a weird knock sound that was tob,fork was banging on transmission was knock sound.
My first thought was rod knock ,,

 

[01yellercobra]

It's just so weird that you hear it through the exhaust and no where else. I've had rod knock and you heard it loud and clear at the engine. Don't think I've ever had a plug come loose though. Closest to that was when my 01 ejected a plug.

 

[CobraBob]

Can you hear it from under the car? Near the muffler? I'm thinking there might be a loose bracket and the rattle is traveling the tubing to the tailpipe. ?? I also thought it could be the honeycomb catalytic converter material breaking apart and rattling. But then you should hear it from the engine bay, too.

 

[2003RedfireVert]

Obviously the exhaust isn’t loud enough…tell him to turn the music up.

 

[Roush6018]

you know when you pop the hood and look at the engine i can hear it missing on one cylinder, its not ticking in the engine bay its misfiring. i hope the muffler does have a loose weld in the baffles. check the spark plugs are all tight, then pull the mid-pipe and start it up with just the manifolds to verify the sound is coming from something in the cylinder head. i think the bottom end is fine, but the cylinder head could be where the noise is coming from. also the check engine light could help you point to which cylinder bank is bad.

 

[5.0 Hatch]

The engine I just replaced had a similar tick but not as distinct as that one. I haven't removed the heads off my old engine to see exactly what it was but I have a feeling it was valve related. I also had an exhaust port soaked in oil so something definitely was going on.

 

[01yellercobra]

It has long tubes and no cats. Mufflers are brand new and just installed. As mentioned it was there before these current mufflers were installed. The trans was also rebuilt a couple months ago with a new RXT and supporting equipment. It was there before all that.

The ticking when he pops the hood is the injectors. The ID's are loud. I have the same injectors and they sound just like that. I do need to pull the plugs to check them still.

I've crawled all over that engine and you can't hear anything up front. I'm not sure we'd be able to hear anything if we fired it up with open headers. But I bet it would sound bad ass.

Unfortunately I wasn't the one to install the headers so I don't know about any valve or port conditions.

The only code that's popped is the P0153. And last week was the first time it's popped. I'd say maybe the harness got pinched, but it ran fine for a couple months after the rebuild.

It could be the head. At least he'll have an excuse to take the next step with porting and cams if that's the case.

Obviously the exhaust isn’t loud enough…tell him to turn the music up.

Lol. It has a full custom stereo in it. My understanding is it's pretty loud.

You guys are saying a lot of what I've been thinking and wanting to check. So I feel better about my train of thought. The car is at the body shop for the next couple weeks. Once it gets back I'll do a little more troubleshooting.

 

[Roush6018]

i have a tool in my mechanics box that goes in both ears and it has a rubber tube about 3 feet hooked to a metal rod. its a mechanics stethoscope. when i have the tool in my ears the running motor sound is quiet, like i have ear plugs in, however ANY tapping noise will be heard in the metal rod ( i think its a aluminum rod) will be heard in my ears. i recommend get one of these tools and place the rod ON the cylinder head near each exhaust port on the side we think has the problem. try to verify the tapping inside the head (possible exhaust valve) before taking the engine apart.

i recommend get the valves looked at and fixed, new Fel-Pro MLS head gaskets and this would be a good time to make the switch to Evans water-less coolant.

i have stock 03 cams and stock heads bolted to a built lower end, and i have so much fun every time i drive it. I also have a RXT and it made my car so much better.