I have a '00 SH Lude with 22,000 Miles on it.
Previously I'd had really bad sputtering while in low RPMs and changed everything I thought would cause this .. and still had it, so I said screw it and just started to finish fixing it up, so I had the exhaust on and it stoped that.. so I guess back pressure was the issue for that.. just thought I'd let you know that much incase the following would be somewhat related..

I have the following Codes:
O2 Sensor
MAP Sensor
A/R Ratio Meter?

Mods: MSD Igniton, AEM : Fuel Rail/CAMS/Pulleys, DC Header.

I've had these codes since I've had the car, It's sat for about year. I've replaced Rear O2, TPS, MAP Sensor, put stock ignition back on. I'm at a loss for what it be causing these codes. The local honda shop told me to check ECU cause even at Idle the car is reading it's at Full load? Gas sucks. Lol.. just looking for some help? Any questions just ask.. thanks.