TAtoad

iTrader: (22)

The answer to this might be on here, but all i found through searching was that i shouldn't drill out the stock hole on the throttle body.

My problem is a high idle, around 1200-1400 when in neutral up until i'm at dead stop. i checked my throttle body, and the hole has been sealed. could this be the cause? i just got this throttle body a week ago, and the seller didn't offer much info on it.

mvvette97

iTrader: (18)

Is this a ported throttle body? If so I would say it's a bad port job and he more than likely was having the same problem. Plugging the hole will do just the opposite of what your car is doing. It must be ported around the blade too much letting too much air in so he plugged the hole hoping to reduce the air flow a bit. So no it's not because the hole is plugged. It would be even worse with it open. Best thing would be to get your money back

TAtoad

iTrader: (22)

it had light hand porting done on the lip surface area, not really by the blade. i would get my money back, but i bought it out of necessity. i got screwed over on a TB trade, and a guy let this one go for cheap. for now this is my only option. my SES light came on, I'll check out what code is given and inspect the throttle body

00pooterSS

iTrader: (40)

IF it started when you got the throttle body then its the throttle body, could also be the Idle Air Control valve, make sure you plugged it in good. If the hole is sealed some one was trying to lower the idle.

mvvette97

iTrader: (18)

well then I would try to adjust the set screw to close the blade more.

TAtoad

iTrader: (22)

yea, it started when i got the throttle body, but while i was without a throttle body i also got a mail order tune. the tuner said he contacted a Z28 owner with the same tune and his vehicle was running well. so i'm almost sure its the TB

408trans_am

iTrader: (263)

post some pics of the tb, and maybe someone here can tell you if something is wrong. I would also try to lower the idle set screw, and also make sure you have the o ring under the iac sensor, if not it will cause a vacuum leak and increase rpm.

TAtoad

iTrader: (22)

i should be home by 6 tonight, i'll try to get those up

00pooterSS

iTrader: (40)

You have to really be cautious with that one, you really should never adjust that unless someone else messed with it, but who knows maybe that is the prob if the previous owner turned it up, but it can cause the blade to bind so you will have to make minor adjustments and see what happens. If it binds when you close the throttle then you backed off the adjustment too much. The best way to do that is to open the blade and let it slam shut, you should be able to roll it open easily afterward. So back off the screw till that happens then adjust it up little by little till it stops binding then stop there. On mine I did that and it was fine unitl I started the car and it would bind again once the blade was under vacuum so I had to run the screw out just a hair more. For whatever reason mine binded after I sent it out to be ported so I had to mess with the adjustment.

And yeah good call about the O ring.

TAtoad

iTrader: (22)

here are the pictures of the throttle body. 2 show where the hole was filled, and the other shows a gap at the bottom of the plate where i noticed and it doesn't close all the way, because the original stop mark is still visible; there's a tiny gap at the top as well. i tried adjusting the screw, but its clogged with some silicon type material, and the few torx screwdrivers and allen wrenches i have don't fit correctly. before removing the TB i ran the engine and sprayed started fluid around all possible air leaks. what do you guys think?

408trans_am

iTrader: (263)

that tb looks absolutely terrible, hopefully you didnt pay to much or maybe can get your money back. Its been either way overported, but i doubt that since it looks like it hasnt been ported enough. I would guess the blade has been "knife edged" and taken down way to much. Either way its not good.

As of now, there is no good fix, you can get a new blade and that may fix it, but they are impossible to find by them selves. Or you can buy a stock unmodified tb, or a ported one from a reputable place.

TAtoad

iTrader: (22)

actually, i agree, it doesn't seem as if its been ported enough, BUT i do believe the screw adjuster has been messed with. where the blade stops, its still a few millimeters from what i assume is the original stop, because there is a ring permanently marked all the way around the inside of the TB which the blade does not reach

masterz28

iTrader: (8)

Yeah the tb looks like it was made of dough. So the space between the blade and bump is visible? hmm I guess like 408 hinted, a new tb is in order. If you want to see where and how the air passes through the tb at night shine a flashlight under it to see an eclipse effect if the gap is wide enough, you would be able to see it.

max1

iTrader: (12)

any-b know where you can get a TB blade>?

TAtoad

iTrader: (22)

What's the exact size for the adjustment screw? most of my tips are messed up and don't grab right

DemonInside

iTrader: (54)

damn that thing is fubar'd

i have my old ported stock tb if you were looking for another, i just went to a fast setup this spring

408trans_am

iTrader: (263)

t15 is the size

TAtoad

iTrader: (22)

thanks man, but im'a try to fix this one, or try my best. don't feel like spending more dough

TAtoad

iTrader: (22)

thanks bud, i'm borrowing a friends set to try to get it right

WS6nJAX

iTrader: (207)

if you cant get it right, let me know. if interested, send it my way and i'll fix it or hook you up with another t/b free of charge. you just cover the shipping. just consider it my way of helping out a Tech member.