von

This is different. Ok I just rebuilt my 7 engine with large streetport...Anyways the car does not make enougf power to idle below 2000 so the TB actually has to have the primaries open , secondary screws open and also the Throttle tightend down to open the butterflys a little more. This way it idles at 2000 but it bounces up and down like as if the TPS was bad alhtough even when set it still bounces ? Isnt this from the TPS not being able to adjust for the Extreme TB settings ?

It bounces up and down 500 rpms .

DC350

dude, just break in the engine first

kep0ne

yeah...the TPS thinks its at the factory position for 1.0, when in reality its at X. adjust your TB as per FSM standards, then adjust your TPS, then go ahead and open the butterflies up.

NZConvertible

Even bridgeports can idle at 1500rpm. If you can't get a 1000rpm idle with a streetport, something's wrong, like a vac leak. Yes, the throttle if too far open for the TPS to read correctly. It's hunting up and down trying (but failing) to get a decent idle speed. As a temporary measure you can unplug the BAC valve so the ECU can't try to control idle speed.