exhaust leak or engine knock
 

I have mac long tubes and two days ago i started to hear a little knock sound and at first i thought it was something hitting on something metal because it had that kind of sound but now i have started to wonder if it is a exhaust leak. It doesnt do it right away when i start the car in the morning but the rest of the day i have this horrible ticking noise. It happens wether the clucth is engaged or not and it speeds up with the rpms. My girlfriend said that it gets really loud when i get on the gas. ( i had her listen as i drove away from her house last night) What do yall think it is? is there a easy test to check whether it is a exhaust leak or not? And what problem in the engine could make this noise: spun bearing, thrown rod....anything?
Thanks

RE: exhaust leak or engine knock
 

sounds like an exhaust leak, make sure your bolts are torqued to specs. and did you replace any of the gaskets

RE: exhaust leak or engine knock
 

yea man totally an exhaust leak. I had the same thing happen to me. If it were a knock you would know. Check the pessenger side, for some reason mine was always on that side, I dont know if its just a characteristic of the beast or if its just my car.

its not a thrown rod, the engine wouldn't idle, it probably wouldn't even run. I guess it could be a spun bearing, but when that happens its more of a rap than a tick.

given that you just put the exhaust on they are going to expand and contract with the heat, until that are broke in. So I'd give it a 90% chance that its a leak.

RE: exhaust leak or engine knock
 

^^ +1 on what they said. I have an exhaust leak. It sounds a lot like a car pinging.

Knock sounds different. Knock sounds literally like metal knocking hard against something else that's metal. It's a horrible sound.

Fortunately for you, and exhaust leak can be fixed. They are somewhat common with long tubes though. And sometimes they do come back after you fix it. But just make sure you replace the gasket and retighten everything.

RE: exhaust leak or engine knock
 

well i got under the car today and tighted everything down but the sound is still there. When i was under it the sound seemed like it was coming from the engine. Could it be one of my cylinder detenating.

RE: exhaust leak or engine knock
 

pinging doesnt really sound like an exhaust leak.... if your car sounds like its pinging.. you might be running way to lean and i would have that checked out... my car was pinging on the dyno and then later i had an exhaust leak the 2 sounded nothing a like....
and exhaust leak sounds like paper flapping in the wind.. pinging.. i cant really explain what that sounds like...

RE: exhaust leak or engine knock
 

is running lean= to much timing

RE: exhaust leak or engine knock
 

yes. if you have like a hypertech tuner or a superchip micro max tuner, or any of those other cheap a$$ tuners.. more then likely your running lean if the tune is installed. if you have an sct tune or diablo tune you should be fine... it usually only happens with the cheapo tuners. because they advance the timing so much its absolutely ridiculuos. Thats why my car was pinging on the dyno. cuz of that crappy hypertech tune.

RE: exhaust leak or engine knock
 

like marbles in a tin can

RE: exhaust leak or engine knock
 

thats exactly what it sounds like.......a ball bearing bouncing around in my engine

RE: exhaust leak or engine knock
 

I've had that noise for years, and every mech told me it was ok. Though no one can explain what it is ?? I just had my car tuned again professionally and it's stil there(so I know it's not a timing issue, I run 93 octance also???)I havn't tightned my MAC LT since the've been on. How the heck did you tightnen your bolts. IM all ears. I can't get a socket in there for the life of me. My noise comes form the drivers side and sounds like it's inside the engine on the bottom half. It almost sounds mechanical.

RE: exhaust leak or engine knock
 

i have a tubular k member so it makes it a little easier but my noise also sounds mechanical

RE: exhaust leak or engine knock
 

I say it's an exhaust leak.

When I had my exhaust leak after I installed my headers I thought I was able to get in there to tighten the bolts.The leverage just wasn't there.I tried to tighten them about 10 times before I pulled the motor.Every time I tightend them I got about 5 turns out of them until I felt that they were tight.In all reality I had no leverage and they were still very loose.Just on the pasenger side though.And leaked only until the engine got hot and the gaskets would expand.It was a nasty ticking noise.

When I pulled the engine I realized that the most rear bolt had vibarated all the way out and the others were still loose.I installed and torqued the headers onto the new motor and installed the new motor with the Headers already on and I have no leaks what so ever.

RE: exhaust leak or engine knock
 

They do sound alike. Or atleast mine does.My exhaust leak sounds almost 100% identical pinging. I've had pinging from to much fuel, and knock from too little fuel/too much timing. When my car was pinging, it sounded EXACTLY like marbles being rolled around in a tin can. And my exhaust leak sounds A LOT like that. Maybe your leak is in a different location, or does just sounds different all together??... But my exhaust leak sounds a lot like pinging.

RE: exhaust leak or engine knock
 

okay my and a friend have completely decided that the sound is not an exhaust leak,......now what else could it be? could it possiblly be a bad coil? the sound is coming from the inside of the engine.....