EGT Question

[mconstable]

Hey All... Lately, when parked waiting for my EGT's to get down to 300, I'm noticing it's taking almost double the time that it used to.

It's across the board, any climate etc.

Just curious what might cause this?

Should I be concerned?

TIA

 

[rbattelle]

When you say "any climate" do you mean anywhere from 20 degrees ambient to 90 degrees ambient?



The EGT gauge will tend to indicate higher temperatures in winter than in summer, because the current generated in a thermocouple is generated in response to a temperature difference along the entire wire, not just at the tip. The voltage reading depends on the difference in temperature. So if one day your actual tip temperature is 300 degrees and the other end of the thermocouple wires (at the gauge) is 80 degrees, the gauge might indicate a temperature of, say, 295 degrees. Then another day if the actual tip temperature is 300 degrees (again) but the other end of the wires (at the gauge) is 20 degrees, the gauge might indicate a temperature of, say, 310 degrees.



Know what I mean? That's why I ask if "all climates" really means "all climates", because if it's 20 degrees colder on average everywhere you drive then you will notice the higher temperatures.



-Ryan

 

[mconstable]

That makes sense... Thank you... I'll pay attention to outside temps and judge accordingly.

 

[wcjp]

I bought a temperature gun for just because. I now use it for all kinds of things. Maybe someone local to you has one to verify your EGT temps.

 

[Badunit]

Also makes a difference if defrost or A/C is on. Mine takes a lot longer to cool off with the compressor running. But the thermocouple answer is probably the correct one.