Recently replaced the whole TB on my 2004 Accord 2.4l with a brand new genuine Honda TB. Still have high idle at startup and once it warms up. I've done the idle relearn process per Honda service manual two times with no change. I'm getting no check engine lights at all. I've done a check for vacuum leaks with a smoke machine with no leaks found. One thing I can think that might be causing this is that on removing the old TB and placing the new one, I had to remove the throttle cables and maybe somehow they need adjusting? They currently have some slack, but it's not excessive and the cables are not tight as to be pulling the throttle body open a bit. Could the factory have set the tps incorrectly? Still need to check those values.

What other things could it be? I've checked to make sure ALL sensors are plugged back in and any hoses are connected to where they're supposed to be. Also, I did not have this high idle symptom before changing it out. Any help would be greatly appreciated. Thank you

 

The 04 might need a scanner to force the PCM to relearn the idle? If you have a scanner that can read some live data, look at sensor data to see if something doesn't make sense, like the PCM thinks the throttle is open.

 

I do have a scanner that can read live data, but can you shed some light on what type of data to look for? I'm thinking data that has something to do with the throttle body?

 

Look at throttle position, accelerator position sensor, map, intake air temp, mass air flow (if you have one), coolant temp. Items that can affect the idle. Maybe something will look way off and give you some direction.

 

Thank you