Ever since I added a full bottle of R-134a to the D (it was empty), to use my A/C in this humid New England summer, I’ve noticed the cooling fan has been coming on a lot more than usual, or more than I’ve noticed in the past, since I prefer opened windows to A/C. I know this is expected when using the A/C, but my main concern is what the temp gauge is displaying.

The temp gauge usually likes to sit in between the mid-point & high-end of the “normal” range, but today it was right on-the-line of normal, ready to cross over into overheating territory.

I was leaving New Haven, CT this morning to head back to Cambridge, MA (~2.5hr drive), and after cruising around Yale to get some breakfast, the temp gauge raised to the high end of normal within minutes; fan goes on and stays on, almost the whole time. I head onto the highway, and after 5min at 75mph the temp gauge lowers to the ½ mark, and is there for the rest of the drive. When I hit toll booth lines it goes up a bit (to approx. ¾), but then cools down to ½ again after a few min back at hwy speeds.

I get home, but have to hit Copley Sq (Downtown), to run a few errands. I unpack, and let the D rest for about an hour, then head out. I keep the windows down and A/C off, but eventually the D warms up to ¾ (according to the temp gauge), and the fan comes on, and remains on the whole time. At the end of the 40min stop-and-go journey, the temp gauge is on-the-line; almost into overheating, fan still on.

Problem…or normal? [FYI, outdoor temp was 80F/27C during all driving condition]

Thanks in advance!

 

You have two issues, one AC related and one coolant related.

Coolant issue first...

Make sure the overflow is full to the right level and make sure the total system is full tot he right level. If the stat is good, re-burp the system to spec. If unknown, replace stat (dealer item only is recommended whereas many aftermarket stats do not have the correct weap hole) and burp to spec.

Let us know how the near overheating issue goes and we can go from there.

IndyDurango

 

Sounds like one of the fans aren't working or you are low on coolant. Ensure the electric fan is working when the A/C is engaged. Electric fan is between the engine and the radiator.

Replace the radiator cap and burp the system.

+1 Indy on the T-stat, but try the easier stuff first.