themealonwheels

iTrader: (20)

I have a 2002 Z28 with a 383 LS6 that's still in the break in stages, it's got about 250 miles on it. The intake is a PP Typhoon 96mm inlet, LS2 style and I had a 92mm FAST TB on it. Well, I saw eBay offering a 102mm for half of what I paid for my 92, so I ordered it and installed this last weekend.

I cranked it up yesterday, and it wouldn't idle less than 2000 RPM warm! The 92 was idling at around 900 warm and no matter how I adjust the stop on the 102, I can't get it to get below 2000. I did reuse the gasket from the 92mm, but that was only because I couldn't find a replacement at my local parts store and it came off without breaking.

So I'm looking for any kind of insight y'all may have. The crank vent tube on the top of the TB has some play, it can be wiggled. If this were the issue, would I throw a code? Also, wouldn't a bad gasket throw a code as well for unaccounted air volume?

Also, is there a place I can get the gasket for a PP Typhoon intake aside from Professional Products themselves? What about an OBX spacer? Since that comes with two gaskets, I'm tempted to throw it in. But what's the ID of one of those? Would I just be putting myself back to a 92mm TB?

sdbrown84

iTrader: (22)

What are your IAC values? If they are maxed, make sure that the plunger is not stuck inside the IAC pathway. I had this problem on one "ebay" throttle body.

Make sure the throttle blade is not "hung" up on anything inside the bore. Move it around and make sure it works freely when the return spring brings it back to rest.

Obviously make sure the idle spring is fully released as well. So you dont modify your idle in any way besides the IAC motor.

themealonwheels

iTrader: (20)

Ooo, good point. I'll check that out when I get home and try it this afternoon. If it is maxed out, indicating an IAC trying to close back but stuck open, should I try modifying the bore or will I just cause more trouble?

What did you end up doing with your throttle body?

themealonwheels

iTrader: (20)

Hey, I just wanted to let you know that this was what happened to me as well. The IAC valve was stuck and trying to move, but couldn't due to a weird size IAC hole. I didn't want to drill on it, so I'm returning it. Same IAC valve on my FAST 92 fit well and the valve is reading a good value. Thanks for the help!