Surging Idle in gear

2007 FORD FREESTAR
105,000 MILES • 3.9L • V6 • FWD • AUTOMATIC
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TRISTANBOYD
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  • 14 POSTS
Idles normal but with a rattling noise in Park and surges when in gear with the brake pressed. If I unplug the TPS (replaced due to a code present) the noise goes away within a few seconds, but it still surges. If I unplug the IACV (also replaced) the surging stops and it runs as it should. If I unplug them both, there is no noise and no surging. There are no codes present since the TPS has been replaced. I'm including a link to a video showing the above.

https://www.youtube.com/watch?v=wJXlaEF2T5k
Mar 1, 2017 at 4:03 PM
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HMAC300
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  • 48,601 POSTS
try cleaning the throttle plate on both sides and shaft area as well as iac hole with choke cleaner. then check for a loose torque converter bolt/nut and loos shields in engine area.
Mar 2, 2017 at 6:58 AM
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TRISTANBOYD
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I took the throttle body off and gave it a thorough cleaning. It was pretty dirty. No change in the surging. Still surges with the IAC plugged in and stops when it's unplugged. We have noticed that it doesn't do it until the engine heats up to operating temperature
Mar 5, 2017 at 10:38 PM
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HMAC300
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  • 48,601 POSTS
scan for codes or have you done that already also check for a vacuum leak. get back to us with any codes. also check duct work between air cleaner and engine if any holes replace it as that can cause it as well.
Mar 6, 2017 at 6:22 AM