Ok dude, calm yourself. You have let your car build up issues and now winter is coming, I get it.
You biggest problem is the thermostat, I believe you replaced it. But, I also am very confident it is now stuck open. Failure of a replacement thermostat after a year is actually pretty common depending on what replacement was used. I'd use either the OEM or Dorman thermostat this time.
And your fuel pressure fault is most likely the sensor, because if you actually have low fuel pressure the car wouldn't run. Take care of the thermostat first, then we can fix the other minor issues.
You biggest problem is the thermostat, I believe you replaced it. But, I also am very confident it is now stuck open. Failure of a replacement thermostat after a year is actually pretty common depending on what replacement was used. I'd use either the OEM or Dorman thermostat this time.
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The car DIC coolant temperature gauge only reads out the "actual" coolant temperature part of the time. It is programmed to read out feel good numbers so people don't obsess over every little change. For the real temperature you will need to monitor the ECT on a scan tool.guage goes ALL the way back to cold. I clear the code and the guage goes back up a hair
I agree the shutter is probably stuck open, but your cooling issue has nothing to do with the shutter being open. There are thousands of cars running just fine without a shutter at all.Maybe the shutter is stuck open and cooling it down too much
And your fuel pressure fault is most likely the sensor, because if you actually have low fuel pressure the car wouldn't run. Take care of the thermostat first, then we can fix the other minor issues.