ok so heres the story. 3 days ago i drove to richmond to trade my si wheels for some gunmetal 16s, and i had just put in my silencer because everyone in my neighborhood had been bitching about my car being so loud. im not sure if thats would be the reason why, but on the way back from richmond, i got until about 30 seconds to my house, and my catalytic converter broke. the neck that is after the cat and connects to the pipe came out. the car still drove fine with the cat connected to the stock downpipe and nothing else, it was just very loud. i couldnt find anything to hold the cat from dragging on the ground, so i went under the car and took it off and took a look to see if i would need a new cat. after inspecting it, i realized when i got my cheap big als piping put on, they cut off the second flange from the cat and just welded the pipe straight onto the neck, but they refused to fix it when i asked them about it. so, i just ran open header(manifold), for a total of maybe 25 miles. i did the best i could not to get on the throttle at all, but i did have to one time. only revved it to about 5500rpms, but i noticed after i did so the car felt a lot more sluggish, even than it already was before without the cat/piping. didnt think nothing of it at the time, but since big als refused to fix the problem, and since i was low on cash, i spent 14 dollars and bought some piping, a connecter, and some clamps and just ran a sraight pipe from the manifold to the 2.25inch piping. got done, started up the car, and it sounded much better. little raspy, but not too loud. i figure cool, problem fixed. so i drop the car off the jack stands and go to take it for a drive to pick something up from the store, and find out the car wont rev above 3000 rpms. it gets there and just kinda studders, almost as if it was at the redline or hitting a revlimiter. what the hell could be the problem? someone please help, i want my car back

 

did you remove any sensors?

 

nope. the car is an 88 crx si with a d16y7 motor, stock manifold and stock cat. no sensors were plugged into the cat that wouldve been able to be removed.

 

not enough back pressure man!!!!!

 

would not having enough backpressure honestly restrict it from revving correctly? i kept the silencer on figuring that would help the backpressure with the straight pipe. anyone else got any ideas?

 

Check the piping from were it broke back, there may be a piece of debrie from the cat or the old pipe in there restricting the flow.

 

you can run open headers w/ a obd0 or obd1 car... i do that at the track all the time...disconnect the cat from the headers and run headers only...if you still have a problem it is not the exhaust...but by doing this this will help elimiate the exhaust/cat being a issue...be sure to completely make sure exhaust is out of way...not remove the exhaust piping, but make sure that the exhaust is not shooting into the exhaust piping....

 

maybe you should try to replace your O2 sensors.

 

TTT

 

do u have a CEL on? if so reset ur ECU. If no CEL it is possible u burnt a valve running open header.