Ported Tb Problem, Urgent
#1
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My buddy home ported his tb for his ls1 and epoxied the Iac area up and put two holes in it just like some of the sponsors do and ported it a bit where the blade meets like a paperthin gap is between the blade and the throttle body all the way around. When he starts his car it idles really high like 1200 rpms and and when he revis it,it sticks at like 2K for about 5 seocnds before it idles back down to 1200. The Iac Count accoring to autotap stays at 0 at idle and has set a ses light.... What size holes should the Iac holes be? What else could be the problem, where there is a paper thin gap between the thorttle blade and tyhe tb could this cause this high idle? Also his car set a code: P0507 Idle System High -IAC Responding
How do we fix this?
Thanks
How do we fix this?
Thanks
#2
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The gap around the edges is what's causing the high idle, just like a large hole drilled in the TB will raise the idle.
I guess you could try to remedy it by covering the hole in the TB up. I'd wait untill some other people offer thier opinions before I messed with it though.
J.
I guess you could try to remedy it by covering the hole in the TB up. I'd wait untill some other people offer thier opinions before I messed with it though.
J.
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Cover the TB plate hole with either JB Weld or stainless steel tape. He's getting too much air through the perimeter of the plate.
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There are 3 circles on the TB blade, 2 of them are screws, the white colored one is a hole that air passes thru even when the TB is closed. By overporting the TB, air is going around the edges and raising the idle, if you cover that hole the idle will be lower. How much lower, I dont know.
J.
There are 3 circles on the TB blade, 2 of them are screws, the white colored one is a hole that air passes thru even when the TB is closed. By overporting the TB, air is going around the edges and raising the idle, if you cover that hole the idle will be lower. How much lower, I dont know.
J.
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I experienced the same problem and jb welded the hole and re-drilled it. Sorry, can't the remember the size right now though, but either way, the car was surging. I was going to drill more but got frustrated and gave up. I'm sure the hotcam doesn't help but I'm pretty sure if you cover up the hole, the car will not idle. You can try coating around the edge of the blade with jb weld and then sanding it down to where you want it, but it's a hassle.