So after I put my BBK off road x pipe on my 01 Cobra I started hearing this rattling noise, thinking it was exhaust I took it to the shop and it wasn't, I even checked, so this only happens at like 2000 RPM and up once the car is turned on for a few seconds, and only when I give it gas, not when I let it engine brake or idle. So I'm thinking Rod knock but wouldn't that be all the time? Oh and I've been running 91 octane on the engines 93 octane tune. So I just ordered a bama 91 octane tune and new spark plugs? Maybe that'll fix it? What does it sound to you guys, thanks.
Rattling noise?
- Thread starter Daryl Mozart
- Start date
If you can replicate this sound in neutral then put it on the lift while someone is under the car.
Yeah did that at the shop, it's definitely not the exhaust, the mechanic said it sounds like it's either coming from engine bay or transmission.
It sounds like exhaust hitting to me.. no other symptoms?
No not really, it's not hitting anything man I even looked at it, nothings touching.
Based on your very first sentence in post #1, I would suspect it's exhaust related. And after hearing the noise, I would put the odds at right around 100% that it's exhaust noise, or related to something you disturbed while doing the exhaust.
I recently hunted down a similar little rattle on my Roush. It took me like three times on the lift to find it. I was banging and shoving the system by hand and all seemed good, but still had mysterious rattle. FINALLY I found where one of the muffler braces was hitting a hanger in the rear ever so slightly. I clearanced it with a little bit of grinding and now all is quiet again.
Dig deeper, look closer, you'll find it.
I recently hunted down a similar little rattle on my Roush. It took me like three times on the lift to find it. I was banging and shoving the system by hand and all seemed good, but still had mysterious rattle. FINALLY I found where one of the muffler braces was hitting a hanger in the rear ever so slightly. I clearanced it with a little bit of grinding and now all is quiet again.
Dig deeper, look closer, you'll find it.
I don't know how that would be even the exhaust shop guy did a full check up on it while I was up on the lift revving it, the noise is coming from like the bottom of the engine, also the weird thing is if I turn off the car and wait a few min and turn it on it doesn't automatically make the noise again, after a few seconds it'll start again, I'm thinking this is a detonation problem due to the tune?Based on your very first sentence in post #1, I would suspect it's exhaust related. And after hearing the noise, I would put the odds at right around 100% that it's exhaust noise, or related to something you disturbed while doing the exhaust.
I recently hunted down a similar little rattle on my Roush. It took me like three times on the lift to find it. I was banging and shoving the system by hand and all seemed good, but still had mysterious rattle. FINALLY I found where one of the muffler braces was hitting a hanger in the rear ever so slightly. I clearanced it with a little bit of grinding and now all is quiet again.
Dig deeper, look closer, you'll find it.
I'm thinking when the off road went on it leaned out the air fuel even more?
So your rattling was coming from the rear? mine is all the way in the front.Based on your very first sentence in post #1, I would suspect it's exhaust related. And after hearing the noise, I would put the odds at right around 100% that it's exhaust noise, or related to something you disturbed while doing the exhaust.
I recently hunted down a similar little rattle on my Roush. It took me like three times on the lift to find it. I was banging and shoving the system by hand and all seemed good, but still had mysterious rattle. FINALLY I found where one of the muffler braces was hitting a hanger in the rear ever so slightly. I clearanced it with a little bit of grinding and now all is quiet again.
Dig deeper, look closer, you'll find it.
Mechanics telling me it's Rod knock, what do you guys think? I just bought some oil additive and plugs, trying everything before having to potentially do rebuild.
As I said, your very first sentence is the biggest clue. You say the noise started immediately after you changed the pipe. So the focus of your investigation needs to be on anything and everything associated with that job.
I've been fixing cars for almost 50 years now. I had two service stations back in the 70's and 80's. I've seen a lot of weird things. Maybe you dropped a nut or bolt down into the pipe and it's in there rattling around. Perhaps you inadvertently moved something else while doing the pipe swap. Maybe you forgot to tighten a clamp. Maybe a clamp has two bolts and you only tightened one.
Basically just retrace your steps through the whole job. Maybe put the car on lift, and run it to create the noise, while someone is down below to see if they can pinpoint the location of the rattle.
Anything is possible, but WHY would it start immediately after you install off-road pipe???????????????????????????
I've done ALL that though that's the thing, I've done it all, nothing comes back to the pipe, I think it might just be a coincidence.
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In to watch, I have the same noise. Told it was a spun rod bearing...
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I've been quoted $3900 for the labor alone for rebuild...
Yup... that's it.
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I've been quoted less, but I'm buying all my parts before we tear it down. I just picked up my Boss 302 Rods and I'm currently looking for some forged pistons. If I'm going to rebuild, I'm building for boost.
Same here, building for boost, atleast to handle 900 hp or so... The labor is insane though :/
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I'm just going to take it slow, get everything I need then attack it all at once. What kind of pistons you going with?
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