I have a 2000 Comptech Sc'd s2000 with Stock pulley and Invidia Catback exhaust. The other day I decided to change the bypass valve from the Diaphram style to a spring activated valve. The car did not like this and was stuttering alot. So I decided to take it off. I changed back to the original valve, but forgot to attach the breather hose on top of the valve. My car was really running like shit, so then I figured that out and got it reattached. I thought everything would have been fine but now my car threw code p1129 which is something with the Manifold absolute pressure. It ran all the way(8Mi) to my house from work with only a few hiccups, but I just went downstairs to start it and it Idles like it is going to stall and It smells like it is dumping fuel. Any suggestions or help would be greatly appreciated. Thanks.

 

May be a long shot but mine had a funny idle forever. I did the map whack and all that stuff. Had misfire codes and everything. It sputtered bad once I put my invidia on. I thought it might have been a bad coil/s so I took them off and decided to check my plugs while I was at it. I had a lose plug. Once I retorqued it all was fine. Good luck.

 

first thing i would do is double check that all the vaccume lines are going where they should be, and are firmly attatched. You had no problems before you changed the bypass valve, and then they appeared. I suspect incorrect routeing of lines.

A map-whack might be a good idea as well.