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Discussion Starter · #1 ·
okay so i may have gotten to the bottom of the problem my car has had for about a year now. the car was shaking at low idle and i think that the mufflers might be the cause. the problem started when it would shake when i would come to a complete stop at a red light or stop and i would fix it by reving the engine and the problem would go away once i would hear a pop close to the driver side muffler. after a couple a months the problem got worse and the shaking wouldnt go away even if i did rev the engine. i did everything possible to get rid of the problem. changed plugs and wires, reprogrammed the pcm, got headers, deleted cats, and anything that would help the performance of the car. so i also noticed that the driver side exhaust wasnt sounding as nice as the passenger side. so i suspected that the muffler was clogged. people on the forum told me that i may have a hole in the case of the muffler. so a couple of hours ago i wiggled the driver side pipes and tapped the muffler. i took it for a test drive and the problem is still there but doesnt shake as much. it responds better and the shaking is still noticable but not so annoying. do you guys think that the muffler is responsible? the muffler are flowmasters and i heard people say that they run on luck, could last as much as 10 years or as little as 10 weeks. so tell me what you guys think.
 

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okay so i may have gotten to the bottom of the problem my car has had for about a year now. the car was shaking at low idle and i think that the mufflers might be the cause. the problem started when it would shake when i would come to a complete stop at a red light or stop and i would fix it by reving the engine and the problem would go away once i would hear a pop close to the driver side muffler. after a couple a months the problem got worse and the shaking wouldnt go away even if i did rev the engine. i did everything possible to get rid of the problem. changed plugs and wires, reprogrammed the pcm, got headers, deleted cats, and anything that would help the performance of the car. so i also noticed that the driver side exhaust wasnt sounding as nice as the passenger side. so i suspected that the muffler was clogged. people on the forum told me that i may have a hole in the case of the muffler. so a couple of hours ago i wiggled the driver side pipes and tapped the muffler. i took it for a test drive and the problem is still there but doesnt shake as much. it responds better and the shaking is still noticable but not so annoying. do you guys think that the muffler is responsible? the muffler are flowmasters and i heard people say that they run on luck, could last as much as 10 years or as little as 10 weeks. so tell me what you guys think.

simple test, disconnect exhaust after "cats" and drive around. problem goes away, then mufflers are to blame.
 

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Any chambered muff can come apart after time. I have an Ultra-flow with a loose baffle that I need to replace that make's noise at times, flow seems ok for now, but one more weld let's go and it could cause a blockage...then I'll HAVE to go buy some Areochambers....damn...lol.
 

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I have an Ultra-flow with a loose baffle that I need to replace that make's noise at times...
Really?cwm6

Ultra Flo? Loose baffle? :confused:




Are you sure you have Ultra Flos?
 

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Discussion Starter · #5 ·
simple test, disconnect exhaust after "cats" and drive around. problem goes away, then mufflers are to blame.

oh snap! i totally forgot that i have cut outs on my car. how the hell did i forget that? lol im going to try them out for the first time today and see if the problem goes away completly. thanks for reminding me.
 

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Discussion Starter · #7 ·
well the cut outs are manual and they are a pain to get to them i got so lazy to try them out that i totally forgot i had them
 

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.....I have an Ultra-flow with a loose baffle that I need to replace......


Really?cwm6

Ultra Flo? Loose baffle? :confused:




Are you sure you have Ultra Flos?

cwm2

Gregg......if you do have Ultra-flos, then your problem is either a loose heat shield or a cat-convertor with guts that are breaking apart.

I'd bet money on that!

KW
 

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The rattle is in the muff, I can bang on it feel it & hear it right at the muff it has Ultra-flow stamped on the case, they were on it when I bought it 5 yrs ago. I guess the cat coming apart could have crap stuck in the muff??? Car is running fine, other than needing a tune - up 108k miles and I think it's still got the original plugs, wires, cat & rotor, and O2's. I'm down to 12.5 MPG in the heat running a/c 100% of the time in stop & go.
 

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The rattle is in the muff.......I guess the cat coming apart could have crap stuck in the muff???.....
Yes.....absolutely!

When one of my cats tood a dump, the guts came out of the cat......made its way THROUGH the muffler AND the pipes......and expelled out the tail pipe cwm2 !

So.....having 'cat' guts in your muffler is very much within the realm of possibility ;) .

KW
 

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Discussion Starter · #11 ·
okay so i havent tested the cut outs yet because it rained like a hurricane this morning but i noticed that the shaking increases when i turn on the AC.
 

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The AC is a considerable load on the engine, so if it has a problem running already then it should come as no surprise that turning on the AC worsens the problem.
 
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