The OP affected the idle symptom issue by only removing a vacuum hose connected to the EGR valve (eliminated the idle problem when warmed up). I would think the OP would be best served by digging into that element first, not the IAC or coolant temperature sensor.Some random guess. Maybe you didn't clean iacv well? Maybe coolant temperature sensor is bad? Look at fuel trim, too much gas or air?
OP, if the engine runs normally when cold, but doesn't when warmed up, and with a warm engine with the engine idling (no foot on the gas pedal), I really don't think your EGR VSV is the problem at all.
I'm attaching a picture of a sticker that has the vacuum routing diagram for a 1995 Camry 5S-FE (2.2L) with California emissions, just for reference. I am also attaching a service manual section from my 1993 Celica service manual - it looks to me like the EGR system on a 1995 Camry 5S-FE is essentially identical to that on my 1993 Celica 5S-FE. If you look first on page EC-38, that page will help you a lot. There is a table at the bottom that ties the diagram boxes labeled (1), (2), and (3) above it. Look at that very closely and spend some time understanding it. I think it will help you understand next steps needed to verify what is wrong.
Note in the table, when the engine coolant temperature is below 131 deg F, the ECU will not supply power to the EGR VSV. That means the EGR valve should be closed when the engine is running, no matter if you are on the highway or have it idling. Next note that when the engine coolant temperature is 140 deg F or above, the ECU may or may not energize the EGR VSV. The engine coolant temperature is that which the engine coolant sensor for ECU is telling the ECU. The ECU will also not energize the EGR VSV if the engine RPM is above 4000. The ECU will also not energize the EGR VSV is the throttle plate is not beyond port E on the inside of the throttle body. The ECU gets that information from the throttle position sensor on the throttle body. The ECU will only energize the EGR VSV when the throttle plate is moved beyond port E on the throttle body.
With all that said, you stated the engine runs & idles smoothly when cold/cool. This tells me your engine coolant temperature sensor for ECU is functioning properly, and the ECU is responding properly by not allowing the EGR VSV to be energized. However, once the coolant temperature is above 140 deg F, the ECU properly removes that restriction on not energizing the EGR VSV, which is also correct. But, the ECU should be not activating the EGR VSV if the throttle plate is not beyond port E (which if it was, the engine should be at a very high idle speed). This tells me you may have a problem with your throttle position sensor, or at least the signal getting back to the ECU. Has your throttle position sensor ever been removed? If it was, it needs to be calibrated when reinstalled to ensure it has the output of a closed throttle plate when the throttle plate is closed. If not calibrated properly, or not working properly, your ECU may be getting a signal that the throttle plate is opened further than it really is. There may be other root causes that produce this symptom, but the fact that your EGR VSV is energized when the engine is in a slow idle (throttle plate closed) tells me the problem is in the throttle position sensor and/or the wiring going to the ECU. The ECU could also be defective in that it can no longer read the position location coming from the throttle position sensor.
If it was my car, that is where I would be focused on right now.
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