Cascade Crew

Xophertony

some of you may recall just after switching to a manual tranny i began to notice that my idle would get stuck at 1000-1200 RPM, sometimes as high as 1600! well, after re-setting my idle speed to around 400-600 (hard to tell with digital dash) today i could physically see the problem. my throttle blades get stuck open. i was under the hood, engine running with the IAC unplugged and as i moved the screw back, the throttle stayed still. i touched it and it snapped too it's new idle position. i redid this a few times and the problem persisted. i got in the car and held the gas to produce 1600RPM and slowly let off the accelerator pedal and it hung, i go under the hood and give it the tiniest tap and it returns to idle position.

well, now i know why the idle is hanging, the throttle blades are sticking open. but i do NOT know what is causing the throttle blades to stick. the spring is tight as hell. i figure I'll oil the moving parts and that will be that. if anyone has any ideas for areas i should pay close attention too i am all ears. or perhaps input from those that have experienced this in the past.

Sellmanb · Member Joined: 30 Nov 2004 Posts: 727 Location: Tigard, OR

I had a pesky one like this on an Astro van last week, try to spray carb cleaner down there, and clean out around the throttle blade. If that doesnt do much, there's probably gunk baked onto the edges of the blade. Take the throttle body off, manually move the blade out, take a screwdriver and chip it all away. Replace TB gasket, and reinstall Wink

DBL_TKE · Posted: Sat Apr 28, 2007 11:43 am Post subject:

I used to have the same problem. I just took some carb cleaner as Sellmanb suggested and sprayed the return spring and took some cloth and tried rubbing away any build up on the blade. Then move the blade back and forth a bunch while spraying a little WD-40 where the prongs of the throttle blade go through the holes. hopefully that'll do it.

Xophertony · Posted: Sat Apr 28, 2007 12:41 pm Post subject:

thanks guys, i thought i was going to have to dis-assemble the whole thing. Shocked

Twilightoptics · Posted: Sat Apr 28, 2007 1:37 pm Post subject:

Also, take your maf bellows off and use some carb cleaner to clean out the black carbon around where the throttle blades seal. Meaning by hand put the throttle to WOT (Engine off of course) and wipe out as best you can both bores.

Plus some oil/WD40 on the spring/mechanism will help.

Might also check inside the car and make sure your gas pedal isn't hanging up somewhere.

90droptoproc · Posted: Sat Apr 28, 2007 4:11 pm Post subject:

ya I would disconect the throttle cable and see if it still hangs up when opened by hand, that should tell you if it is the TB or something upstream

if it does turn out to be the TB it could be the bushings that the blades ride on coundn't it?

just a thought, I have never dealt with this

aaron_sK · Posted: Sat Apr 28, 2007 5:25 pm Post subject:

I did the same thing on my IROC. I just removed the entire TB and cleaned it with a rag. After that I lubed the spring and the pivot points, let it sit overnight to let the lube soak in, then reinstalled it.

Taking the TB off is nothing if you've done the coolant delete mod. Just two wires and four screws. You can even reuse the gasket if it's in decent shape.

Xophertony · Posted: Sat Apr 28, 2007 5:32 pm Post subject:

i hit it with TB cleaner, a bunch of black shizzle flowed out the front. it seems fine now, but a few days of driving it will tell for sure.

aaron_sK · Posted: Sat Apr 28, 2007 5:34 pm Post subject:

Tony, are you still running a stock EGR?

Xophertony · Posted: Sat Apr 28, 2007 5:55 pm Post subject:

aaron_sK · Posted: Sat Apr 28, 2007 6:23 pm Post subject:

That can clog it up. My IAC was messed up because of the EGR crap in the intake.