2G Pulsating idle 100 to 2000 RPM now it idle at 500 RPM

[Turbo bob]

Idle air control valve has been removed since there's an aftermarket intake. Not sure why I have this idle issue runs perfect once you're on the gas wondering if somehow the o2 sensor could possibly cause this issue changing fuel mixtures. I was thinking potentially maybe a TPS sensor any help would appreciated

 

[dwb]

You need an ISC (IAC) for proper idle control. Factors like electrical load, engine temperature, AC (if still installed) all affect the idle and it needs a method to allow more or less air past the throttle plate.

 

[Turbo bob]

It's worked perfectly fine for 5 years just not good for cold starts to play with the throttle

 

[dwb]

Low idle = not enough air. Adjust your BISS to increase idle speed.
High or pulsating idle = too much air. Adjust your BISS to decrease idle speed. If the BISS is bottomed out, check for post-throttle intake leaks. If you have the FIAV still installed without a blockoff/bypass plate, that can contribute to high/pulsating idle.

 

[Turbo bob]

Around fine for 5 years no issues then it was pulsating high and without any changes decided to idle at 5:00 or 500 RPM so obviously it's not an adjustment something is out of whack I'm thinking o2 sensor just looking for a little advice here

 

[dwb]

Around fine for 5 years no issues then it was pulsating high and without any changes decided to idle at 5:00 or 500 RPM so obviously it's not an adjustment something is out of whack I'm thinking o2 sensor just looking for a little advice here

Go ahead, throw parts at it.

 

[Turbo bob]

I'm not a Ford dealership mechanic that's why I'm asking to see if there's any advice from seasoned members