hey i am new to this site i have a 99 civic si. my civic is not running good right now and i have no clue what it wrong with it. me and my buddy was putting on a header for it and he cuts my o2 sensor then it started running bad. i can not rev past 2 1/2 rpm. i already got a new 02 sensor and it did not fixe it then i thought it might be the ecu so i got a used one and it still runs the same. dose any one know what could be wrong with it?

 

Is there a CEL?

 

Sounds like you need a buddy that knows what he's doing.

 

yeah i don't have the car here with me right now

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by -Todd- &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like you need a buddy that knows what he's doing. </TD></TR></TABLE>
Really...

Cut the o2 sensor? Why? Even if it was too short, they sell extenions that work awesome and are fukc-up-proof.
If it was working before...why bother getting a new one?
Why buy a new ecu...instead of just fixing the problem? Of course the 2nd ecu would act the same - you have a problem!!!!!

When you get to the car, do this:
https://honda-tech.com/zerothread/1901557

Then come back and get some help from those of us that know something