My throttle body would have to be blipped to close fully. I thought it was worn out so I bought a new BBK 52MM unit. The new unit does the same thing AND sticks bad causing the car to not engage power smooth. I tried adjust the idle screw out but the sticking, harsh power enagement, and high idle remained.

Start the car, open the throttle body by hand about a 1/4 inch, and watch it stay there as you let go. Then when i shut the car off the throttle body "fully" closes by itself instantly. This causes a nasty high idle which requires a blip to fix.

I don't know what to do here.

 

do you have a spring on the throttle body also how does it open and close with the car off does it snap back closed

 

snaps back perfect with the car off. I think this throttle body is suffering from vacuum lock.

 

well 2 things i can recomend. First check the throttle cable they can stick a bit. Second check your TPS as it may be getting stuck binding things up and sending information the ECM that would indicate that the throttles still open somewhat.

 

Sounds like it wasn't designed properly. Throttle body (and carb) blades/shaft are supposed to be offset. This exposes more throttle blade opening on the up side so that vacuum pulls them shut.

RBob.

 

Well design might not be the issue as it was doing it with the stock one just not as bad. It might be an IAC problem but I have no idea how to test that. The car idle fine when I fully close the throttle blades by hand so who knows. Maybe I just need to drill a small hole in each blade.

 

The stock one probably had the throttle shaft bores worn. This causes the blades to not seat the same each time. And allows air to leak in past them.

What you described in your first post about the BBK points to not having the blades/shafts properly offset. For now I would try adding a carb style return spring for a little more tension. Although I'm not sure if that will make the pedal-push release worse or better.

RBob.