Throttle Adjustment

[britishrallying]

Hi,

Ive currently got my throttle bodies off, ive read loads on the forum and in the service manual of adjusting the butterflies:

http://www.gtirworkshopmanual.com/default.aspx?v=223

But how do I know if the butterflies are shut correctly? they look shut now before adjusting them!

Is it a case of pouring a small amout of fuel down the chamber and see if any leaks out?

On the second pic the rear stopper lever is clearly seated, no gap between them....

All this just to get my idle down to 100rpm :lol: replacing the injector seals as well..

Noticed a few rubber caps missing off the throttle balancing screw as well:

Gaz

 

[stumo]

i would adjust the stops by doing what you said (using liquid) or just getting them to close without sticking when you open the throttle.

once you've adjusted the individual stops the rods will need to be adjusted....(probibly just the rear one but it's worth checking both)

 

[britishrallying]

Decided to have a fiddle adjusting the butterflies tonight, noticed this when I caught it against the light:

I loosened rear stop lever stay, and adjusted till the throttle opened without sticking but you can see a small amount of light around the butterfly, some are worse than others, I have cleaned the bore and the edge of the butterfly so its not sticking on dirt..

Is this normal or should it be a tighter seal?

 

[PobodY]

I think they used to have seals on the edge of the butterflies; and they've worn away over the years. I'm sure the ones Shaun had looked like that too, but at one stage they probably closed completely.

 

[MacK_Gtir]

would this cause high idle? I stripped and cleaned my throttle bodies and now its idling at 2000/2500 rpm

 

[Trip]

more air ingested = higher idle,

When the TB's are shut, the ecu activates the bypass soleniod to act as a source of air for the engine to idle (otherwise it will die). I am not sure if the ECU can controll this bypass soleniod in a variable way to adjust for the worn butterflies.

 

[PobodY]

Sort of - that's what the adjustment screw on the IAC does, rather than the ECU doing it.

 

[Spikey]

Mine hold fluid for a good few minutes when i did a test a few weeks ago.

 

[skiddusmarkus]

would this cause high idle? I stripped and cleaned my throttle bodies and now its idling at 2000/2500 rpm

This is why I never stripped mine for fear of making it worse due to me not really knowing what I am doing and winging it.My theory is that therewill be a small amount of oil lining edges around the butterfly which will help seal it and cleaning that away will let air past it.

My idle is okay when cold but once its warmed up it hunts and makes it look like I am revving it like a right nad when waiting in traffic.I've replaced visible vacuum pipes, swapped the idle valve(took 3 hours with with engine in, my wrists said ouch) for another I stripped and cleaned up, used new inlet manifold gaskets when engine was out and messed about with the idle screw and it made no difference.Can a remap just tell the idle to feck off and make it stay at 1k rpm regardless?