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Discussion Starter · #1 ·
Just installed my tune and cai from Brenspeed last week, I had a little less than half a tank of premium left, still haven't filled up. I noticed the first day I put the tune and cai in that after I got on the pedal and went full throttle, any other time I would hit the gas there would be a backfiring/grinding noise from the exhaust, then about five minutes later it would go away. Kind of sounded like my exhaust pipes had gotten loose again or something a sort of grinding noise but it could be backfiring, and if they were loose the noise wouldn't just show up for a bit after full throttle.

I dunno if I need to put more fuel in for the car to suck up when I go full throttle or what? Originally last week I thought it was my air intake making the grinding noise but it sounds like it's from the rear of the car. It didn't happen all weekend but it started up again today after I gunned it for a second and spun the tires to get around a Hyundai on the way to work. I would stop at a light, give it some gas and something sounded nasty back there.

Any thoughts guys? Never happened before the tune/cai.
 

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Keep in mind that the CAI is processing more air. More air in=more air out. That might be all that you're hearing.
 

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Discussion Starter · #5 ·
Yeah, I figured that might be what it is.. shouldn't I be hearing it while I'm on it though? Or is it trying to process all the air out after I get off the gas and start going slower and it makes my exhaust sort of.. fart it out?
 

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Discussion Starter · #7 ·
Ah.. sounds like a nasty metal grindy noise though.. didn't know how to describe it. I figured it was from the CAI. Any other things I need to watch out for? Like my shirt getting stuck to the filter or something when I have the hood up, haha?
 

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Yeah, I figured that might be what it is.. shouldn't I be hearing it while I'm on it though? Or is it trying to process all the air out after I get off the gas and start going slower and it makes my exhaust sort of.. fart it out?
That sounds like what you're hearing.
 

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Ah.. sounds like a nasty metal grindy noise though.. didn't know how to describe it. I figured it was from the CAI. Any other things I need to watch out for? Like my shirt getting stuck to the filter or something when I have the hood up, haha?
Just keep an eye out for any check engine lights. Usually if there's a problem with a tune they will start to show up withing 2-3 driving cycles.
 

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Discussion Starter · #10 ·
That sounds like what you're hearing.
Really? Didn't know it would make my exhaust sound like that. Figured it was from the CAI but it was a cross between a backfiring/metal on metal noise. I do have a muffler delete so I'm bound to have weird stuff going on back there from time to time. At least it goes away fairly quickly after accelerating again. Any other stuff I should worry about with having a CAI? Like getting my t-shirt sucked onto the filter when the hood is up? Haha
 

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Discussion Starter · #11 ·
Just keep an eye out for any check engine lights. Usually if there's a problem with a tune they will start to show up withing 2-3 driving cycles.
Well last night my dad went around a corner sort of aggressively in the car and the TPMS light came on and said the tire pressure was low. We checked it at a 7/11 air pump and the tires just needed a bit of air but the light didn't go away and was on this morning. There was a bit of a drop in temperature in Florida though. It went away around noon though.
 

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I had a noise like that and when my car back fired it blew my high flow cats out the back. It could be parts of it blowing around. Listen under the hard acceleration under the dash. Mine was annoying.
 

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The cats could be comming apart with the new CAI and no back pressure for no mufflers.
 

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Tap the cats with a rubber mallet and listen for any rattling which would indicate that the substrate is coming apart.
 

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The cats could be comming apart with the new CAI and no back pressure for no mufflers.
That's the first thing I thought of as well. You might also check if the over axle pipes are touching the diff cover. Under hard acceleration they might touch and cause a metal on metal sound.
 

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Discussion Starter · #16 ·
It didn't do it today, might have been something to do with the weather. I don't think having a muffler delete would do anything to the cats when having a CAI/Tune as many people have had this set up for a long time and had no ill affects.
 

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It didn't do it today, might have been something to do with the weather. I don't think having a muffler delete would do anything to the cats when having a CAI/Tune as many people have had this set up for a long time and had no ill affects.
The muffler deletes aren't going to hurt the cats at all.
 
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