I have been working on my car trying to get it to idle lower... I run the AEM EMS so i have control over the idle valve. I can shut the idle valve all the way but the car still idles at at about 1500 RPM. Its a H22, but I have a B-series STR throttle body right next to me and its pretty much identical.

I cleaned the STR out, and tapped holes and plugged them, so there are no more internal air passages, that brought the idle down about 700RPM from where it was last night.

However, with the plate fully closed, there is still air seaping thru the butterfly, i can hear it when i put my finger by the throttle plate on the sides, you can hear the air sucking around my finger.

I think the problem is that the throttle return spring just isnt tight enough to close the thing hard and seal it well.

Anyone else have issues with this?

I have stock cams, and there is no reason that I dont think I should be able to idle at 1200RPM at least. The injectors are too large to idle lower than that, they wont open with less then a .8ms pulsewidth (1000cc HKS), and at that pulsewidth and lower RPM its gonna be really rich. But I would be very happy with 1200. 1500 is just barely too high.

Charles


Modified by mister2racer at 8:54 PM 5/30/2004

 

If it is not closing then I would say adjust the throttle stop screw, aparetly you have it adjusted to let air in. If you don;t adjust that and only mess with the idle air valve it is still going to leak or let air in. Right under the pully is the throttle stop screw. Good luck!

 

Boostfed: The adjustment screw is no longer even in the throttle body, it is closing as far as the spring pressure will close it.

When I force the plate closed by hand, the idle goes down to about 1200. Its definatly not closing all the way.

 

common str problem

 

what should I replace the thing with? What is the size of a stock ITR throttle body? Or are there any other pimp *** CNC ones?

 

ericks

 

how about the JG throttle body? Friend of mine has one that he said I can try... does that one have any known problems?

 

trying a JG one wouldn't hurt..... RPM services are pretty good too. on the STR throttle body why don't you try put a spring return kit. its just a simple spring that helps the throttle plate close. you can find one of those at autozone.