a little more info on your setup is required.
1. what engine management are you using (stock inj fmu missing link, 450cc afc hack, larger inj w/ tuneable ecu)?
2. what d16 do you have?
3. any cel?
4. how much deflection is on your throttle cable (none, 1/8", 1/4")?
5. what throttlebody are you using?
any other info you have will help in the e-diagnosis...more is better than not enough.