P1281 Error Code

Strazi said:
upper radiator hose was uncomfortably hot to hold onto at this point. I just don’t get it.
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That does not mean much. Mine is the same way, but I used an gun to measure the temperature and it was about 180. I have a mopar Thermostat I'm installing today, is that what you did?

Motorad is the one I had a problem with! I'm installing a MOPAR today!

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Actormike said:
That does not mean much. Mine is the same way, but I used an gun to measure the temperature and it was about 180. I have a mopar Thermostat I'm installing today, is that what you did?

Motorad is the one I had a problem with! I'm installing a MOPAR today!

View attachment 423895
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Can you link me where you got a mopar one? I can’t get one for the life of me all I keep getting are these motorad pieces of junk, even when they say they are mopar.

In terms of a infrared thermometer yes, I used one to validate the temperature my PCM was reading out. I’m borderline debating buying a thermostat made for the 4.0 and cutting it to size.
 
Strazi said:
Can you link me where you got a mopar one? I can’t get one for the life of me all I keep getting are these motorad pieces of junk, even when they say they are mopar.

In terms of a infrared thermometer yes, I used one to validate the temperature my PCM was reading out. I’m borderline debating buying a thermostat made for the 4.0 and cutting it to size.
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It just arrived and it's stamped MotoRad. Probably the same crap as the one I got from NAPA!

 
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Actormike said:
It just arrived and it's stamped MotoRad. Probably the same crap as the one I got from NAPA!

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I swear the only logical issue that would cause an engine to run cold is a bad tstat or the ECT sensor reading the wrong temp, which I don’t think mine is.

I’m like 0/7 with these motorads
 
Strazi said:
Went through a dealership to get mopar and what do you know, a motorad came in the packaging…

I put in the new thermostat and same issue, only got up to 177 and the upper radiator hose was uncomfortably hot to hold onto at this point. I just don’t get it.

I’m praying there is just trapped air at this point but I doubt it. I’m going to lose my sanity.
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It fixed my problem and the Mopar now is made by Motorad. When you pulled out the old thermostat was it stuck open like in my video?

 
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Actormike said:
It fixed my problem and the Mopar now is made by Motorad. When you pulled out the old thermostat was it stuck open like in my video?

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No it wasn’t. Originally my issue was the ECT sensor, which I replaced and that code went away. Then this code came up and I’ve tried at least 6 different thermostats and the issue isn’t going away. I checked the voltage across the ECT sensor port and it was right around 5V, which from what I’ve seen that is correct.

At one point I checked resistance of the ECT and it looked like it was in the correct range of ohms for the temp it was at.

I’ve used a infrared thermostat and my OBDII read out and the temperatures are close in value.

If I leave my Jeep idling it will get up to temp and the electric fan will kick on right around 220 degrees and cool it back down to 210.

What is strange to me is that the upper radiator hose gets hot way before the thermostat should open, right around 160 degrees.

The coolant level is full and I doubt air is trapped. Even if air was trapped the infrared should catch that the ECT temp would be off.

Im just lost at what it could be at this point. Im going to try sticking a resistor in the ECT sensor plug to see if the fan kicks on. If this happens that tells me it shouldn’t be a PCM/ wiring issue.

Any suggestions?
 
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