94 celica ST idle flucation, cant get the idle to be steady. Options

[rapid36]

Hi everyone my 94 celica ST has a idle fluctuation when im in gear and have the fans on. when the fans go off i idle at about 1k. normal idle in park with no fans or accessories on is about 1.5k which I know is a issue, I replaced the fuel filter, spark plugs and spark plug wires, o2 sensor, throttle body and TPS from another celica but I dont think I aligned the TPS correctly? Do you think this may the cause? If so does anyone know how to properly re adjust the TPS sensor onto the throttle body?

https://youtu.be/mmk4e4pkoo8

Im also getting a code 25 which says "The air/fuel ratio feedback compensation vlave or additive control valve continues at the upper (lean) or lower (rich) limit for a certain period of time." And noticing this I had another set of fuel injectors that was off my old celica which ran just fine and put those on so I dont think its the injectors. Any help is appreciated.

This post has been edited by rapid36: May 17, 2016 - 11:43 AM

[Box]

It won't run at its full potential with a vacuum leak, it can make a world of difference if the leak is bad enough.

[rapid36]

It won't run at its full potential with a vacuum leak, it can make a world of difference if the leak is bad enough.

Thanks!! ok so heres the update... Cleaned the IAC valve without removing the IAC valve and by spraying carb cleaner into the port on the bottom of the inside of the throttle body, I just removed the sensor part that is held on by a few screws, also had to take off the throttle bracket and then I was able to have access to the screws for the IAC valve then as I sprayed carb cleaner in the throttle body port I was moving the IAC valve back and forth, and after cleaning it, it did make a difference but I dont think the valve is able to open quite all the way, so I will be replacing it with the other IAC valve I have (which feels easier to move than the other IAC valve which is why I think the one thats on there isnt able to open all the way). Im pretty sure the problem will go away completely then.

As far as the lean condition is concerned I took a fog machine I had and hoked it up to the vacuum line from the brake booster and fogged out the intake system and found smoke coming out by the back of the throttle body, so when I replace the IAC valve I will be adding RTV gasket maker to the back of the throttle body gasket, this should seal it. I will also use RTV gasket maker on the IAC valve to make sure there are no leaks there either. This should eliminate all of my problems. I will post back with any updated I have.