Now engine temp gauge reading low

[joecool911]

I posted a question about my fuel gauge reading higher than normal last week. Sounds like the sending unit in the tank is bad.

Today my engine temp is reading about 25* low. Pretty simple and cheap to change thermostat, in fact I have one one hand. Then probably looking at the temp sensor in the head. But now I'm becoming skeptical about these two conditions happening at roughly the same time. About a week apart. Engine operating normal it seems. Just wondering if these two conditions could be related in a weird way?

[Yankneck696]

Check your 5VDC bus to see if it is up to snuff.

Ed

[Mopar1973Man]

Check your 5VDC bus to see if it is up to snuff.

Ed

 

Also check to see if there is a error codes for 5V issues.

 

Check battery ground. Only the main cables supplies ground for the ECM, PCM and VP44. All the other body grounds are for lights and other sub-systems.

[joecool911]

I have no idea how to proceed with this. Other than checking cables.

[joecool911]

Wel this is interesting. Decided to pull the thermostat since it's so easy. High dollar cummins $60 thermostat failed. So the items listed above are not related. The disc on the bottom of thermostat fell off. Hope there is nothing else besides the stainless disc floating around to get caught somewhere in the cooling system. Had an old Napa thermostat in my spares box. Temperature normal now. $8 thermostat saves the day!

Glad I didn't spend a bunch of time on electrical issues! I did buy a digital volt meter and no alternator noise issues.