Stalls at idle?

Try cleaning throttle plate on both sides and IAC hole with choke cleaner. throttle body may be worn with as many miles you state. then check fuel pressure with a gauge it may be low, auto parts rent gauge and you may need an adapter to check it.

See link.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Should be 43 psi key on.

and

https://www.2carpros.com/articles/stall-at-idle

Please run down these guides and report back.

Hi and thanks for using 2carpros. Com

The issue can be caused by many things, so we need to try to eliminate as much as we can. First, when it stalls, does it start right away? When it is running and not stalling, are there any issues with engine idle speed? Does the vehicle need to be fully stopped for it to stall or can it happen while you are still moving? Have you checked for engine vacuum leaks, fuel pressure or is the check engine light staying on while driving?

This problem can be transmission related, idle air control related, fuel pressure related, an engine vacuum leak issue and so on. Let me know the answers to my questions so I can better guide you.

Take care,
Joe

Welcome back:

Okay, I have one more questions. When it was jerking, did it feel like a vehicle with a manual transmission coming to a stop without depressing the clutch? Sorry, that's the best way I can describe it.

Let me know.

Joe

Welcome back:
This can be a few things. My biggest concern. It is related to the transmission torque converter. Since the check engine light hasn't come on to indicate an engine related problem, and it doesn't happen all the time, the first thing I want you to do is check the transmission fluid. Make sure it is clean and full. It should be a redish color. If is good, then I would suggest removing and checking the torque converter clutch solenoid. It is located in the transmission on the valve body and can be accessed by removing the transmission pan. Here are the directions for checking it. Picture 1 shows its location and pic 2 are related to testing.

Remove torque converter clutch solenoid valve.
Check resistance between two terminals.

Resistance: 10 - 16 Ohms

If this proves good, there may be the start of an issue with the torque converter itself. However, if the solenoid is locked, the transmission will not disconnect from the engine when stopping.

Let me know if this helps.

Joe

Inspect and test the idle air control valve-auxillary air control valve ( IACV-AAC ) and also test the throttle position sensor, also the EGR/PCV valves to include a fuel pressure check

No problem. Let me know how things work out or if you need anything.

Take care,
Joe

Is there still smoke from the throttle body? Was the smoke from the engine (intake) or a component on the TB? How is the engine running?

Can you tell me where the smoke is coming from? Also, were there issues with the TB prior to the replacement of the computer? Have you checked to make sure the fuel pressure is within the manufacturer's specs and not too high as a result of a bad pressure regulator? The reason I ask is because a TB just doesn't go bad from one day to the next. Unless there was a problem with the TB before the computer was replaced, I really don't think it has gone bad. Rather, something is causing it to dump too much fuel or the new computer is causing issues.

First try cleaning out the throttle body with some carb spray and a rag. If it still des it the IAC motor might be giving up on you. Any check engine light?