Some of you may have seen my thread on installing a 70MM throttle body on my S2K, well I have got that done and I am now seeing a high idle issue. The throttle body is a 72MM inlet and 70MM where it bolts onto the intake manifold. The Idle screw is turned all the way in, there is no gasket leaks (tried 2 gaskets to verify), and the throttle plate is not held open by the cable or by the adjustment on the throttle body. TPS and MAP sensors are both set properly and giving off proper readings. It is idling at about 2200 Cold, and then 1400 warm. If I plug the 2 ports inside the throttle body to the venturis, I see idle drop to about 900. I am just wondering if anyone else has seen idle issues or if this is just me that is having problems?

PS: It's an STR throttle body.

 

Have you set the throttle position sensor correctly?
Also, does your TB connect to the stock intake manifold?

I was going to do the same, but now I put back the stock TB and I am looking for a spare manifold to machine it so that it does not have that "step" that would hurt the flow more than doing anything else...

 

did you note the initial readings of your TP sensor with a multimeter? I had high idle issues untill I adjusted my as close to stock as possible

 

I'd lightly loosen the tps and move it up and down to get the idle set right when I did my tb I had to keep turning it down to looked lower then stock but got it to idle fine