i put it on and for one the engine light came on. also the downpipe when i give it a little bit of throttle makes this weird noise. kind of like something is loose or rattling. maybe something inside the downpipe is fluttering? anyone have any idea's or run into this problem before?

 

The check engine light is normal.... did you make sure you tightened up all the bolts... that seems to be a problem with their products!

 

header to dp is tight and the dp to exhaust there is a minor leak however i don't think that is the problem. it's really tiny and i don't think the air going out would make this noise. it sounds like it is coming from the flex part. something inside there or something in the hi-flow dp?

 

Hmm, well if there are rattles it's because it's loose... comming from the flex pipe??? I'm stumped on that.... Just make sure everyrhing is tight... if it sounds like something comming from it take it back out and look it through....

 

I have the same problem, not too happy with this product and will be getting rid of it as soon as i can. All my bolt are tight ( have to keep tightening them as they don't like to stay in)and there is nothing loose underneath the car so all i can think is something inside but not sure what either....really annoying!

 

sounds like a tiny rock is inside. it is really hard to describe it.

 

Their flex pipes are known to do that. It goes away after awhile.

 

it's only when you go into boost or start to give it a decent amount of gas right? like normal driving 3rd or 4th gear give it gas to catch up to speed and go past 0 into boost it makes it and sounds horrible, right?

you sure? i got this dp from a guy who used to have a cobalt and just got it from him. he prob had it on his car for like at least 10k miles i think

 

I have gone through 2 of there dp's all from the flex's breaking....

 

I have a zzp downpipe with cat, been on for over a year now.. it's the only product from them I haven't had issues with!

 

so anyone have any idea's of what i should do? take it off and check? before i put it on i could shake it and something sounded loose inside

 

[QUOTE=1^up;3031769]it's only when you go into boost or start to give it a decent amount of gas right? like normal driving 3rd or 4th gear give it gas to catch up to speed and go past 0 into boost it makes it and sounds horrible, right?

Makes this noise right from start up....like there is something major loose, but i have checked so many times and everything is tight under the hood and under the car....can't send it back as this car is my daily driver and can't afford to have downtime with it (plus live in canada, major pain to send back).

 

well.. im on my second down pipe from zzp. Im running there shorty header with 3inch downpipe with high flow cat. I have had nothing but problems. rattles all the time, cause the cat rubs against the heat sheild.. almost like it was not bent properly. so i get stupid exhaust rattles all the time, even my magnaflow exhaust does not even fit properly, rattles near the rear, i think my car is built weird lol

 

sucks. i got both my dp's for free. the first broke at the flex part from zzp which was a catless dp. now this 3" catted dp. i am not even sure if i am gaining power from it

 

It's all normal. The check engine light is because you have no cat. There are 2 fixes for that.

1. HPtuners
2. You can get a O2 simulator....http://www.o2sensorsimulator.com/

As for the raspiness. That's because you have no cat. You will not be able to get rid of that sound. BUT, you can reduce the sound. On the redlineforums, there is a guy that heat wrapped his flexpipe and he claims it reduced the raspiness in his exhaust.

Your welcome

 

The Code is Not Normal.

The code your getting is more than likely A Converter Efficiency code, which means the cat is not doing it's job.

This is common on cheap off the shelf universal cats.

The factory cat has more Flow area than any of the So Called High flow Cats

We made 403 rear wheel hp with the stock cat on Janazzos car, More To Come with a small change in our Turbo Kit.

We recently tested the stock cat against an off road pipe on ShutZeros Car, and gained nothing exept quicker turbo spool up.

Which Proves there is No real HP gains from Aftermarket Cats or Catless Down pipes.

The Supercharger Is the Dictator of Power on the LSJ.

 

I'm a firm beliver that if its installed correcty the engine light won't come on, and you won't hear any strange sounds. I installed my ZZP downpipe myself, no engine light, no leaks, no problems. I also have helped others install them with no problems. Except that time I got the bungs mixed up. haha put the sensor in the 02 spot. Ended up getting a check engine light. Does your have the extra bung for wideband?

^ I have to disagree with the post above. The ZZP highflow cat flows better then the stock set up. It has been tested on a flow bench before. However, I do agree it could be a cat problem.

 

it is a 3" catted dp. it has a cat. lol

 

He has a Catted Down pipe

 

no extra bung for wideband.

 

Same as 1^up....3" catted d/p (but i didn't get an engine light).....and it can no where near be described as a raspy sound.....it is a definate rattle sound like something loose (metal hitting metal).

 

my bad, i thought i read catless, lol

 

i lost hp with the high flow cat but for some reason it was a wreck from the getgo. i cut it out and now the car has a bit more top end....

but i will try that header wrap on the flex pipe idea cause i hate the way the car sounds

 

have the same problem sounds like
when the car warms up it kinda disapates alittle bit but its still there
ive gone through 3 catbacks 2 dp and 2 headers the only thing left to change it the manifold gasket
thats the only thing i can think of that could be doing it
and yes a manifold leak would sound like its comming from a flex pipe
so if you didnt replace your manifold gasket with the new header that might be your problem