Changed plugs Wed. Pulled out of garage around front of house parked, fine. Next morning going to meeting, won't remote start. Key started and running very rough missing 1-2 cylinders. Stinks bad. ETC warning indicator on. Got to go to meeting. 5 mi. country,8 mi. interstate. Running bad all the way. At least it would reach 60mph. 2hr later come out of mtg., starts and runs fine. 2mi to interstate, accel. up on ramp, and nearly dies. Tach showing 1800, but no power. ETC warning now flashing. Pull to side, WOT gets 2000rpm max. Shut off, restarted, runs fine. Never any check engine, no DTC'c new or history. Protective plastic tip of IAT sensor broken off, sensor looks good. If bad should throw code? Replacing sensor and checking socket today. Any other ideas?

Thanks, Jim.

Take to dealer - new vehicle - can't work on like old stuff.

Do not trust local dealer. Bought at dealer 50mi away.

ETC is "electronic throttle control". If you had a decent scan tool you should be able to see both commanded and real throttle openings. I have an OBDLink MX which works with my laptop and would help a lot in a diagnosis like this one.

In the meantime, disconnect the battery for 30 minutes or so and reconnect. Sometimes these modules just get angry.

A bad IAT sensor would make it run quite rich, but again the scan tool would tell you what it's reading.

Thanks Duster.It is intermittent. Has not come back after the 2 incidents described. I have a decent tool, AutoTap, about 10yrs old. When connected I saw TB opened I think 15 deg. Opened to I think to 30* winging throttle.
Asking what to suspect.

Thanks for response.

Jim.

This has worked for me on OBD2 and up Rams:

Turn the key on, no-start postion. Slowly push the throttle to wide-open and slowly release back to zero. Do it three times. Shut the key off.

Wait a second or two and fire it back up. Drive.

This procedure resets the Throttle position sensor.

I know yours is drive-by-wire, but this is worth a shot and costs you nothing to try.

If it doesn't work, disconnect the battery as mentioned for 20 minutes. Hook back up and it will go into "re-learn".

Trip to the dealer would be next.......

As I have said, it is fine now. Intermitant, throws no codes. Looking for suspects.

Speaking in generalities newer cars will go into limp mode when the computer can't verify the position of the throttle plate, or it is not responding to a position command. It may be the throttle body itself, or it may be the position sensor built into the throttle body.

Did you replace with the factory correct oem copper spark plugs ?

Any issues with the coil pack plug boots when you removed the upper bank ?

Yes Mopar boxed plugs, no upper bank, 5.7.

That uses two TPS sensors in the electronic throttle body as they work opposite of each other. One has the volts increase as the other has the volts decrease and they use two for back-up to be sure its right. I have been away from the dealer since 2011 but we did have some bad throtle bodies a few times and I believe they have to be replaced as a unit as I dont think you can get any seperate parts for the ETB. We had a tool that would record all the electronics that I would use on cust cars with intermitant problems as I could actually put it on the vehicle and give it to the cust. All they had to do was press the button on the switch I would put in the vehicle when it acted up and it would record the electronics and many times helped me fix these part time problems that never seemed to act up when it got to the shop. I would download the recordings and then diagnose them. Ron

JTEC can be reset by undoing the negative cable, then holding the key in the start position for 20 seconds. I've always wondered if that works on the NGC or later stuff