Exhaust pops

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Apex3
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Exhaust pops

Post by Apex3 »

I don't know that this is actually exhaust related, that's why I'm in the engine section.

My exhaust pops sometimes, it'll do it if I'm coasting and just push down very lightly on the gas to where the accelerator is just engaged, it also does it sometimes when I get on it in first a little bit and then shift to second.

It's the same kind of pop you hear from the catless cars like racecar/rally car style. I assume I'm running rich for some reason, but I'm not really sure. The engine is stock, aside from the snorkus delete. I also don't have a muffler, the problem became apparent when I took it off, right now it's just a pipe in place of a muffler. It may have been doing it before but the stock exhaust is too quiet for me to know. I don't have a BOV or anything, and it's stock boost, stock intake

Also maybe related is a small vacuum leak, I'd fix it if I knew where it was, I just think that's what it is because it idles like it.

Any ideas? Or is it normal when you don't have a muffler? haha
adema2626
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Post by adema2626 »

I would say this is normal. Mine did this when I had a 3in exhaust from the turbo back. These cars run rich in general. It's just the extra fuel igniting in your exhaust.

It will destroy your cat, if you have one. But other then that it wont do anything.

It's really fun when your driving by some one and you do it. Scares them a little haha.
-Aaron
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Apex3
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Post by Apex3 »

Yea, I love it, haha, I just don't wanna break anything, not too concerned about the cat, if it breaks I get to take it out and make ~$200, win win, just gotta be sure to register it at school again where there's no emissions tests.
DLC
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Post by DLC »

When my 00 GT was popping a lot, it was followed by a faulty knock sensor. I'm thinking that the timing was a bit too far advanced, and with it running lean, it was chatty.

After the new sensor it quieted down a lot. Might be worth looking in to.
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jefferson
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Post by jefferson »

There is a good chance that you have a small exhaust leak that is letting in some air on the overrun. That will cause popping too.

Jeff
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LookAsubie
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Post by LookAsubie »

Mine does the same thing at the exact same times you mentioned..

but my car is catless 3" from the turbo back.

Its pretty normal and nothing to worry about at all.
and i think it sounds pretty sick :-)
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Legacy Konig
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Post by Legacy Konig »

I don't know man, any noise other then engine noise would seem bad to me.

I don't think any popping is good.

...Unless you're talking about that popcorn popping noise you can make cars with headers or without mufflers make.

That.... "Baa-bi-dah-baa-bi-dah-bah-bi-dah" noise you get gearing down for the stop sign?

..or something else :shock:
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Apex3
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Post by Apex3 »

Well since I don't have a muffler I have to assume that's it :D it's the same kind of popping a race car makes when downshifting but obviously not so loud and obvious.

I think I'm just not gonna worry about it. When I can afford it I'll start replacing sensors
douglas vincent
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Post by douglas vincent »

Most likely you have a leak somewhere in the exhaust system that can PULL in air, ie oxygen, that then can cause the unburnt fuel to ignite.

God knows, thats my problem!
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