I recommend the no-cost, idle reset procedure. Nothing to lose. Here it is again.
1) Disconnect the negative battery terminal, or
...1.1) Optionally, disconnect the keep alive memory connector in the small wire also landed to the negative battery terminal. You can then wait the 10 minutes, reconnect the plug, and go to step 6).
2) Turn the headlight switch ON.
3) Wait at least 10 minutes.
4) Turn the headlight switch OFF.
5) Reconnect the negative battery terminal.
6) Start engine normally (never press on the gas pedal when starting a fuel injected engine).
7) Allow idle speed to settle for at least 30 seconds.
8) Within 70 seconds after starting the engine, apply all accessory loads that the engine will see at idle. Do these concurrently.
...8.1) ATX SHOs only: shifter to DRIVE.
...8.2) Climate control to MAX A/C.
...8.3) Headlight switch ON.
...8.4) Turn steering wheel 1/4 turn side to side.
...8.5) Press brake pedal.
9) Do not turn off the engine for at least 5 minutes.
10) It is preferable that the car be driven immediately after setting the idle programming.
11) While driving, allow the coolant temperature to rise to the normal range.
12) Run the car through its entire performance range.