I have done the S5 UIM ontop the S4 UIM, used the s4 throttle body. Runs great and all but do have a question on the idle adjustment. Can you who have done it get the idle below 700 rpms? I have my idle at approx 750rpms but cannot get any lower adjustment as the idle screw will not turn down anymore. I am curious if its due to the different pathway provisions for vacuum/MOPair/idle air on the throttle body and on the s5 plenum/s5 throttlespacer(black thing) or some tiny vacuum leak becuase I am using a federal s5 intake with all the extra vacuum nipples(extra ones plug tightly, i hope)

Thanks

 

750 is where its supposed to idle. You dont want it lower than that.

 

The question is what the range of the idle screw to go below 700rpms with the S5 UIM swap, not what idle speed I should be at....

 

there is a differnce between s4 and s5 uim? oh dear.

 

Yeah seriously. Be happy that you did a swap and it's idling right.

 

People would kill to be able to idle at 750!

 

mine idles at like 700-900 since i took the AC/CV off when i put on my road race header. it wavers.
im going to restate what has already been said. 750 is stock warm idle. why do you want to adjust the screw lower?

 

Can you who have done it get the idle below 700 rpms? I have my idle at approx 750rpms but cannot get any lower adjustment as the idle screw will not turn down anymore. I am curious if its due to the different pathway provisions for vacuum/MOPair/idle air on the throttle body and on the s5 plenum/s5 throttlespacer(black thing) or some tiny vacuum leak becuase I am using a federal s5 intake with all the extra vacuum nipples(extra ones plug tightly, i hope)

BOLDED thats why

 

I did the swap, and idle at 450-500. Have you made sure your throttle plates are closing all the way?

 

Thanks Jaguarx7 for the confirmation. They do close all the way, this is with the throttle cable off. It is most likely a tiny vacuum leak somewhere then

 

I still don't understand why the idle needs to be or should be or should be able to be lower?

I get it now! He wants to know what's the lowest and highest possible idles are such that he can confirm that his idle screw approximates that range.

 

I posted the question to find out the how the S5UIM swap should act. The black piece that goes in between your throttle body and the intake have pathways inside built in for the idle, vacuum, and atmosphere. The black pieces are different between series in where the placement for the pathways are located, and the biggest difference is that the s4 piece has a provision for atmosphere for the MOP lines.

Since they are different, I wanted to make it clear if it would affect my idle adjustments or if I just have a vacuum leak somewhere else.