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Dodge 4.7L rough idles when hot

On a hot day, when iddling for some minutes, my Dodge Dakota 2001 4.7L engine starts rough iddling, looses rpm, and afterwards sometimes has no power, almost like a limp mode, and a few minutes of driving it snaps back to normal,

Engine light comes on as soon as it starts rough iddling. After a few days of driving the light goes off again, until the next incident.

I have spent over $400 on a new Oxigen sensor, a temperature sensor, cleaning fuel rail;, new air filter,a new injector. couple of garages. A new software download with a service bulletin. All with no good results. Help

Very seldom does throwing parts at a problem fix it.

A proper diagnosis is needed and first you should have the OBD11 scanned for a code(s).

The problem MAY be a faulty IAC valve. BUT that’s JMHO.

Sorry I diddn’t mention that the scan code shows “Oxigen sensor heater circuit failure”, however, the test made by the software to check the heater circuit is done only when outside temperature is below 37 F. So something smells funny with the problem and the code…
I’ll follow on the lead of the IAC valve.
Thanks for the reply.
Unfortunately, or fortunately, in the winter the problem does not appear.
It is definitively related to or affected by high ambient temperature.