Just wondering if anyone might know about the coolant system on the JK. I had the engine light come on Saturday while I was out. I checked the codes when I got home and it was popping a P2181, which is Coolant System Performance. The dealer was unable to see anything wrong, and cleared the code, and was not able to get it to come back.

The service department told me that what might cause that (other than a computer glitch), could be a sensor or thermostat. Anyone ever had this issue or have any ideas of what to keep an eye on?

By the way, the Jeep's performance never changed when this happened, so I am wondering if it was a computer glitch.

Oh, and after doing some searching on here, I noticed "check engine light" issues with several members after using Shell gasoline...which I filled up with the day before this happened.

 

did the dealer have your jeep for the day? because according to the service manual they need the jeep to be cold to diagnose it.

the set condition for the code is
PCM recognizes that the ECT has failed its self coherence test. the coolant temp should only change at certain rate, if this rate is to slow or to fast this fault will set. Two trip fault, three good trips to clear.

its either the ECT sensor, thermostat or Powertrain control module