Is the butterfly valve in the throttle body supposed to be closed shut?
 

I had high negative LTFT (-10 to -15%) on idle and off throttle for a while when I had my Perrin CAI installed. Also had rpm dips when I came up to a stop that would blink off my DRL LEDs. But now it's back to normal (positive 2-5%) with my stock airbox installed.

During the swap, I noticed the butterfly valve in the throttle body was slightly open. Picture is attached. Is this normal?

http://imgur.com/cFZvyWk

You need to scale the MAF when running an aftermarket intake such as the one from Perrin.
http://www.ft86club.com/forums/showt...01#post1842501
http://www.ft86club.com/forums/showthread.php?t=83945
IIRC it is normal for the throttle to be open a little bit.

Well, I know nothing about throttle bodies on these cars ........ but, I would speculate that it would be normal to be partially open sometimes ...... if it were completely closed ...... how would the engine get any air ...... :popcorn:



humfrz

Took the words right out of my fingers @humfrz

yes, the throttle body stays slightly open. I had the same concern the first time I took mine off

The neutral position for the throttle body is slightly open. This position is close to where it sits at idle.
The ECU can fully close it. Also, it can go past fully open...