Exhaust popping

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Jeef

NO MA'AM
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Quick question. ON my 2006 Silverado I had a 3in exhaust from the cat back. It was fine for 4 years and then the muffler and tail pipe rusted out. Being unable to get the stock exhaust out of storage I put a 3" single inlet and single outlet muffler and a 12" stretch of pipe with a turndown on the end of it. I had this stuff hanging around so I am keeping it ghetto temporarily. When I down shift or even get the revs up over 2500 then hit the clutch to shift, or just slow the truck down with a higher gear the exhaust pops constantly.

What causes the popping? Can this cause engine damage?
 
My car does this. It pops randomly if I'm letting off the gas, and backfires really loud if I get it high up in the rpm's and push the clutch down. It did it a little when we put the straight exhaust on it from the cat-back, and now it does it all the time with the bov on it. I'm not very mechanically inclined, so I'm not going to try and explain why it does this, because I can't remember, but I do know it won't cause damage.
 
Stock from the cat up and the cat back has a 3" by 2 feet or so intermediate pipe, a dynomax superturbo muffler and a foot or so of 3" pipe with a turn down.

I don't mind an occasional pop but it is annoying. I just don't want to damage anything, no money for an engine swap at this time.
 
My car does this. It pops randomly if I'm letting off the gas, and backfires really loud if I get it high up in the rpm's and push the clutch down. It did it a little when we put the straight exhaust on it from the cat-back, and now it does it all the time with the bov on it. I'm not very mechanically inclined, so I'm not going to try and explain why it does this, because I can't remember, but I do know it won't cause damage.
that's because you have a turbo car with a MAF sensor.... normal.


Jeef, it's probably just a shoddy conection somewhere leaking and causing the bubbling. When i had a hole in my truck exhaust, it did the same thing.
 
that's because you have a turbo car with a MAF sensor.... normal.

Yep- mine pops and backfires cause we changed exhaust and am running a bov. My car needs recirc and when it doesn't get it- it complains. No biggie. Sometimes yes, it gets annoying, but I have learned how to shift and clutch to avoid the obnoxiously loud backfire when it's inappropriate- and any other time it's just funny.
 
Stock from the cat up and the cat back has a 3" by 2 feet or so intermediate pipe, a dynomax superturbo muffler and a foot or so of 3" pipe with a turn down.

I don't mind an occasional pop but it is annoying. I just don't want to damage anything, no money for an engine swap at this time.

You probably don't have enough back pressure and when not under load, it vaccuums and creates the popping.
 
i agree with slammed and i think its normal with a free flowing exaust. just gona throw this out there so correct me if im wrong but a maf car with a bov instead of a recurc valve doesnt that throw off the a/f ratio
 
It's just unburned fuel that got metered out to the engine and it can't burn since you closed the throttle and put less air through it... depending on engine management, a lot of cars do this. I loved this "problem" on my Civic when I was running the monster GSR block- every time I shifted at full throttle I'd get a little fireball out the back. If I slowly let off the gas and coast, I would get a popping rumbled until everything stabilized.

Nothing to worry about. You just hear the popping more since it's a more open exhaust than stock.
 
It's just unburned fuel that got metered out to the engine and it can't burn since you closed the throttle and put less air through it... depending on engine management, a lot of cars do this. I loved this "problem" on my Civic when I was running the monster GSR block- every time I shifted at full throttle I'd get a little fireball out the back. If I slowly let off the gas and coast, I would get a popping rumbled until everything stabilized.

Nothing to worry about. You just hear the popping more since it's a more open exhaust than stock.
+1

But, most modern fuel injected vehicles will turn off the injectors when you are completely off the throttle and still in gear.

So, in my car, if i let completely off the throttle and leave it in gear, it only pops once, sometimes not at all.

But like Cal said, it's just unburned fuel hitting hot exhaust parts. And you hear it more with less muffling/short exhaust
 
Really if you just do a tune up, it should go away. My accord with a gutted cat, and catback
does this now because my o2 sensor and TPS is bad.
 
just gona throw this out there so correct me if im wrong but a maf car with a bov instead of a recurc valve doesnt that throw off the a/f ratio

Nope :) I have a DV (diverter valve) which would be a recirc BOV and it does not throw the a/f off. If you have a regular BOV it may throw of the a/f just a bit but it wouldnt be enough to ruin the engine though.The only main concept on the DV is that it allows you to stay in boost longer between shifts and not as loud :ph34r:
 
Put the stock exhaust back on, no popping. It must have had a hole before the muffler. A week before Christmas the intermediate pipe snapped in half.
 
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