[/align]I have a 2000 civic si i just did a motor swap into it and on startup it idles sort of ok but if i touch the gas it dies. if it runs for about 15 secs the idle and gas peddle gets better and the gar runs perfectly fine i just replaced the tps because i broke the last one and replaced the spark plugs.Any ideas on what it could be.

 

More information might help.

What engine did you swap in? At what rpms does the engine idle on a cold start up versus when warm? Is the Check Engine Light ON?

 

air leak somewhere along the way?

 

I swapped the stock into it b16a2 and its just really boggy on startup like not really an idle but goes up and down between 0 and 1000 rpms or it dies like its not getting gas but it is i just replaced the tps and fuel filter still nothing and yes the check engine light is on but it has always been on i got an aftermarket intake and that caused that i need help fast its been a fun project i put the interior and the motor out of my recked si into this stripped one the motor cranked fine in my wrecked one before i pulled it now it wont i replaced the plugs cause they got water in the holes could that possible be the problem the plug wires got wet i get the front bumper in 2 dasy thats the final thing i need for this project to be finished. Consted a lil less than $2000 and the body is perfect. Oh and the engine idles at 2000 or a lil higher on cold and warm and i cant idle that down the idler screw is all the way in and the throttle cable is lose im putting fuel injector cleaner in it today casue the motor set up for a long time so mayb that will solve the problem.Thing is it started fine a month ago in the totalled car in the new one it wont start right. What could of got wet and messed up on the motor.PLease reply fast.