I am 16 and just bought a 1984 camaro z-28 305 with carb. I am haveing a problem with the idel of the car. I ran the code and it said it was the throttle position sensor. So i had the carb rebuilt and a new sensor put in. But i still have a bad idel at start, but when i put the brake on it gies away and after a little time of the car running and it happens in park, drive or rev. if i let off the brake the car wants to take off on its own. You can watch the gas pedel move down on its own but when i put the brake pedasl on the idel comes back down and when i release thr brake it takes off on its own again. please help thanks

 

i'd be looking at the throttle linkage on the carb and the throttle return spring. could be that theres not enough tension on the spring to release the throttle all the way, or if the spring even got reconnected when the carb was put back on

 

Do you have cruise control? May be acting up. Check for vacuum leaks.
Oh and it is posible that the TPS needs to be adjusted.

 

Hi, yes it has cruise control. I was working on the car today and i get a popping sound in the box under the hood with the cruise control stuff on it when ever i tap the brakes. And when i have my foot on the brake pedal the car runs great . I will look at what you both told me to and i will have some one look at this box by cruise control and see what its called. Thanks

 

Thank, it was a problem with the cruise control transducer assembly. Pick a unit up from junk yard and now it runs great.

 

I have an 83 z28 camero that had the similar problem, try disconecting under the hood your cruise control unit both plugs going into the unit. see if this cures the problem. they had problems with defective curise control units. please let me know if this helps.