I have an 03 cobra with an aftermarket throttle body with a densecharger. It idles way to low. You have to leave it started for awhile or it will jus shut off cus of such a low idle. The throttle return spring, i guess you call it im not to sure(whatever brings the throttle back to idle), doesnt work very well i guess. I had tried putting to springs on there or atleast this guy at a shop i kno did. When there was two springs it idled fine, but i opened it up on the highway and the wire had got caught in the spring and it was stuck wide open. so the second spring came out. any suggestions on how to get it to idle higher?

 

a tuner should be able to do it, or I don't know if your car has it but there may be a screw to adjust where the throttle plates are during idle, I would check for that