Plenum Pan replaced truck won't run - Update Fixed

I need some help figuring out what I disconnected or failed to reconnect.

The story: I had oil loss and the plenum pan gasket failed. Took the weekend and I replaced the gasket. Put it all together and let the silicon gasket cure for 24 hours as per the instructions.

Today, I topped off the fluids and started the truck up. It won't run. If I sit in it and keep some pressure applied to the gas pedal it will run. I get a check engine light and as soon as I let off the gas it stalls. It is a quick stall, no sputtering or stuttering just a quick die.

I had a friend get in it and had them run the truck while I listened to it, I could not hear anything abnormal.

I can't find anything that is not connected.

Any hints or things I should look at would be greatly appreciated.

1999 Dodge Ram 1500 with a 5.2 liter Magnum.

When my 3.9 did that it was a failed IAC motor.

Check the plug in on the IAC. It is the sensor looking thingy on the rear of the throttle body.

You could spray some WD-40 in there throught the throttle body also.

It was indeed the IAC. I looked and it was not plugged in. I plugged it in and it made no difference. Threw a new one on and it is running really well again.

Thank-you bobby66 and HRDave.

The only issue left is a check engine light, but I will run it in somewhere and get it diagnosed if it does not reset on its own.

Probably from the IAC being un plugged. Un-hook the batt, touch the two wire ends together, let it sit 5 minutes and hook it back up. That will clear the IAC code.

If most likely loss it's idle memory when you had the battery unhooked. Try keeping it running and slowly remove your foot from the gas pedal may take a few minutes. Some times when you hook the battery up the idle motor retracts and is slow to extend back where it was.Carbon build up doesn't help it's respond either.