I too had the same problems your describing(same symptoms and problems) on my 06' PT. Sometimes intermittently. Felt like it was gonna die and performance just wasn't right, engine light coming on then going out a day later. Alot of clicking going on under the hood. Been in and out of dealer 5-6 times in the last couple months. They had a hard time figuring it out. It was throwing wierd codes too. (Like Code 9118)
So here's all they did:
1. New plugs
2. New Wires
3. New a/c compressor
4. New fans
5. Fuel Flush
6. Cleaned T-Body
7. Told me to use better gas
8. Fan Control Module
All that, and it was still happening...heres what they did that finally fixed it!
1. Replaced upstream Oxy Sensor
2. Replaced downstream Oxy Sensor
3. Replaced MAP Sensor
BINGO!!
No more clicking, no more stalling out, Idle is now normal, No compressors coming on wildly, performance is back. I'm Cruising again!
Hope this helps someone!