slik98z

I installed my ported and polished tb today in my 98z28 m6. install was a breeze, took my good ol time, made sure i kept anything out of the intake, make sure everything was snug and what not,
but when istarted upthe car, the rpms climbed really quick to 1500 and stayed there. then after a few minutes the rpms would fluctuate up and down about 100 rpms in each direction of 1500.

the hole in the throttle blade seemed to be slightly larger than the one on my stocker. i measured it and its about 1/16 of an inch larger (if my dad was reading the tool he used correctly).

does this sound like i just need to reset the pcm or is this tb not going to work on my car?
thanks
Travis

Ferocity02

iTrader: (60)

Use the idle adjust screw to lower the idle. It might have been opened by the previous owner. Also, the larger hole can do it too. I think the fix is to remove the tb, and fill in the hole with epoxy, then drill out a smaller one.

theblur98ss

iTrader: (71)

There is an idle screw on the TB. It adjusts how much the cam is open at idle. It sounds like that needs adjusted. The slightly larger hole could effect your idle a bit too but it just may make it choppy.

black00TA

iTrader: (3)

sounds like a little more air is passing through that TB at idle than the previous one.

LittleDonny

Make sure the TB to manifold seal is good and tight - you might be getting unmetered air.

Mike K.

like the others have said, adjust the idle air screw or you can always swap TB blades if the hole is just too damn big.

slik98z

to swap the blades would i just unbolt the torx bolts on the throttle cam (i think thats what its called atleast)? where is this adjusting screw?

Thanks for teh replies, i put back on my stock tb for now, and the idle is back to normal. The hole in the other one is definately larger, 3/16ths by my measurements. I do idle slightly high anyhow, about 900 rpms. if i can keep the idle to around 900, as long as im not stalling out that would be what im shooting for, if it makes it kind of choppy it might just as some decent idle noise to the hooker catback and off road y pipe

Thanks again
Travis

01 Red WS6

iTrader: (4)

When I put mine on I had a similar problem but I just rest the pcm and it works fine now. Yours may be the idle screw.

slik98z

thanks guys it was the throttle screw...it was put in upside down (well atleast compared to what my stock tb looked like), adjusted it a little and bingo now the idle is right on.

only one other problem. the coolant lines that go to the throttle body, they are leaking where they meet the throttle body. should i just do the throttle bypass mod and clamp the ends of the tb?