i just got my downpipe installed yesterday, and i drove my car all day yesterday and today, it sounds awesome.
everything was running good . unfortunatelly my check engine light came on tonight ,the car is still running smooth i don,t see any problem with the car. i lifted the car in my garage to check if the 02 sensor on the dp came loose, everything was in place .
whats the deal , its pissin me off.

 

i forgot to mention that i know a lot of people that had downpipes on their srt4's for years and never had a problem. why me!

 

i don't know but will be glad to find out...

And let me ask a stupid question... Does the downpipe remove the cat? do you just pu that on in its place???

 

i put a straight pipe instead of the cat

 

does it make it much louder???
is that not why your engine light is on??? doesn't that second o2 sensor check to see if the cat is working or not. I know that in some cars that is why there is two sensors, one before the cat and one after to ensure that there is a significant difference in the gasses going into the cat and the gasses coming out... but i really have no idea that that is why your light came on, but if you say others have done it, then ?????????????????????????????? I will still be anxious to hear everyone elses response...

 

The light came on because it is reading that the cat is no longer working or isn't even there. If you want to run without a catalytic converter your gonna need an O2 simulator to keep the computer happy and seeing what it wants to see.

 

i went back to the shop today and he connected the thing to the computer and it said that the cat was missing, so he told me that i need an o2 simulator as u said (roadrunner). he told me that the o2 simulater is a 70 bucks piece. is that right?

 

actually all you need is stage 1 and it will take care of the problem. no need for an o2 simulator. the stage computers are designed so that you can run catless and not throw a code, as they look for the first o2 sensor and do not rely on the second. this was done on purpose as there is a cat-delete pipe that is available from mopar performance for use with stage 3r (although any stage can use it).

 

The O2 simulators go for $45 and up, here is a link to the Casper O2 simulators: http://www.jegs.com/cgi-bin/ncommerc...28&prmenbr=361

 

What would've helped your cause in the first place is knowing that what you were installing was actually depeleting you of a catalytic converter. Whenever you see the CEL light come on check for codes. Find out what code its throwing i.e. P0302 (2nd cylinder misfire) and then post it up here, one of us will find it for you.

You can leave the car without the cat, but its probably not the best idea until you get a staged computer like PSI chick said