[jfivesix]

So we had some real crazy showers here in CA and unusual cold and I had my car sitting for a bit.

I turned it on and started driving within 30 sec and had the common issue where the oil temp wasn’t coming up fan started running and then when I checked codes thermostat was stuck open.

Cleared codes and it was cool for a bit but we had more cold showers and such and it happened again.

I cleared it about a week ago and it hasn’t came back since…

Is this a warning sign and should I go ahead and replace it or am I fine? I have had no issues overheating.

[Billfitz]

You need to code to see your coolant temperature. That way you'll know if it's coming up as it should. if not replace the thermostat.

[jfivesix]

I’ve been checking on Bootmod3 and it has been so far. Around 225 or about oil temp level

[Billfitz]

If it ain't broken you can't fix it.

[jfivesix]

Got it , but any idea why it could get stuck open?

[Billfitz]

Stuff wears out. Thermostats are constructed so that when they fail they're supposed to remain in the open position. The engine will run cold, but that's better than overheating. Yours may be in the process of wearing out, or it could have been a fluke. That's why you want to be able to see the coolant temperature, so if it happens again you'll know it in real time.

The thermostat on my N20 is subject to an extended warranty, 10 years or 120,000 miles. They had to do that due to a high failure rate. It would be worthwhile to see if your N55 has similar coverage.

[jfivesix]

Ah makes complete sense.

I’m out of luck on the warranty but might as well order a new thermostat and waterpump(might as well preventatively)

Thanks!