Get the dongle and an app like Torque. Setup a connection and select the parameters:
- long term fuel trim bank 1
- short term fuel trim bank 1
- long term fuel trim bank 2
- short term fuel trim bank 2
Run the engine idle, note the values. Rev up to 2,5k and note the values. Post here

 

What is it doing when starting cold without touching the accelerator?

Does it run at high idle until warming up some and then the rpm drops?

IAC comes to my mind.

 

...or a vacuum leak. I've been starting the engine with disconnected hoses on the upper intake, it immediately revs up. But it should throw the code. Maybe it does, but the light isn't working. That's why I believe a good point to start is to check the trims.

 

yes exactly this what I notice when I drive >>> ((run at high idle until warming up)))

 

Too bad that IAC does not sent a feedback to ECU, so You can't lookup the value. It has 4 pins and consist of two coils. You can measure the coil resistance. Each pair should give around few Ohms (sorry, I don't remember an exact value).

 

First two pins give 45 ohams
Second two pins 0 ohams
and it has 3 pins not 4 pins

thank you

 

I don't have the Jimmy wiring, but in case of a three-pin setup, You have:
- one common line
- drive up coil
- drive down coil
45 Ohms is fine for a coil resistance, but zero Ohms isn't. For me it looks like one of Your IAC coil is shorted, therefore the IAC motion is one direction only: it opens but cannot shut.
You may post the wiring diagram if You find any, but also checking the resistance of an IAC at a supplier's is a good option too.

 

IAC wiring

George

 

His one is a 3-pin IAC. Most probably the two coils are internally connected at one ends and are outed with one common line.

 

Thats the only diagram that I have. It is for his year but apparently there are variations.

George