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Discussion Starter #1
Recently I noticed as the revs are coming down (usually in the 2300 range) I'm now getting like a gurgling noise. It's not loud backfiring but I'm not sure why it just started doing this. Is this something I should be worried about?
 

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normal like Zab said. pretty much any car thats a standard will do this when engine breaking(or that i have seen/heard). the louder the exhaust the more you will here it, so generally on stock exhaust you wont notice it much.

i personally love how my car will gurgle and pop, make it sound mean.
 

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if you just started hearing it id look for holes in the exhaust. mine started getting really bad and when i had it on a lift i found that my muffler blow apart at the seam
 

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Discussion Starter #5
Oh yea don't get me wrong, I really like the sound of it lol. I'll have to go under there and check over the exhaust and make sure there are no cracks or holes. Thanks for the responses.
 

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Even my brother's miata does it lol
Even with the stock 1 1/4 stock exhaust
 

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I miss that sound. My MS3 pops but not continuously
 

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Yeah, I always have wondered what is different in the tune of cars that pop on decel. I've been looking through my AP software and don't immediately see anything that could induce it. Oh well.
 

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It might just be the overall design. SRT4s pop like crazy, Japanese cars don't seem too as much as US and Euro but it's alright, MS# sounds godly while at WOT
 

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Yep.
 

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The 2,300rpm (or there abouts) is because that is where the fuel injectors are turned back on from the fuel cut for decel. Almost (maybe all) modern cars cut fuel on decel ... what need is there to waste fuel, engine braking will keep the engine live, adding fuel would slow the decel process which is not what the driver intends.

The variations of noises, pooping and backfires is largely based on the spark timing under decel. If anyone's old enough to remember, you can get some pretty cool flames with a distributor by playing with base timing. Say 16* base on a SBC, when you decel from 5K it'll shoot flames. Same concept applies to all cars.
 

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Wouldn't retarded timing cause lots of popping? Or I guess low timing, at least.

Don't know how the SCT software is, but I can only edit low throttle/CL timing and the table starts at .31 load, which I don't think you'll get during decel.
 

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With SCT you can adjust down to 0 load, actually it's .100 to 0. And you can adjust that range using various scalars.
You can also change the Lambda during decel, the fuel cut RPM and load along with injector turn on load/RPM.
 

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Discussion Starter #15
if you just started hearing it id look for holes in the exhaust. mine started getting really bad and when i had it on a lift i found that my muffler blow apart at the seam
Good call. After taking a look, hole in the flex pipe. Looks like I'll add that to the list of things to fix [wrenchin]
 

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The sound is usually a leak toward the front of your exhaust system where EGT's are still really high and you add fresh o2 to the mix. You get some nice popping on decel. I've a Vortech and ORP and mine sounds like a desiel exhaust break on Open Loop Decel.
 
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