I'm in SoCal; it's been ridiculously hot over the last couple of weeks (105+ for all of last week). My Alpha runs between 195 and 210 (per Torque app) all day long, with the A/C on. Only time I've had to shut the A/C down was a few years ago, driving slowly in a parade (pulling a Boys & Girls Club float/trailer) during 100 degree weather. Even then, it only got to about 220; temps dropped when I turned the A/C off.

 

It's 105 here with very low humidity around 12%. I just changed out my t stat and added 2 bottles of Royal Purple Ice then filled the rest with Dexcool 50/50. Let it idle waiting for the t stat to open to add more coolant. 15 minutes later and temp at 198 never seen the fluid drop. Put the cap on and took it for a drive. Temp never dropped, kept climbing. 10 min ride and the temp stayed around 215, once it hit 220 at a stop light. The temp did not drop when I was moving about 55 mph. It hovered right around 215 the whole drive. Came home pulled the hose out and cleaned the radiator thinking it was clogged. 10 min later started it, temp at 160, idled 5 min temp was at 208. Revved the engine to about 2800 rpms and the temp came down to 191. Released the throttle, 2-3 min later back to 208. Same revved and came down to 191. How can I tell the fan clutch is bad? Could that be the problem?

 

Appears to have air in the system /low coolant. Recheck coolant level in radiator when cold.

 

Just checked this morning (cold motor.) Fluid in reservoir was low. Topped off. Will drive later today.

 

Remove cap on radiator cold and make sure coolant is full. You made need to run a few hot cold cycles before all the air is out. That's why professionals use the funnel I posted above, quick way to remove ALL air from the system.

 

Took it for a drive yesterday after changing the spark plugs. The ones removed had a huge gap. It was above .50. I couldn't even measure it. The temp climbed to 195-197 and stayed there. Ran so much better. Throttle response was great. Thanks for all the help.

 

You got the air pocket. Now, just monitor full level cold:

 

Maybe spoke to soon. Went to eat this morning. It was a 15 minute ride there temp was same around 197. Hour inside. Drive home climbed to 215 and stayed there. Checked the coolant reservoir level when I got home and it was 3/4 full. Once it cools I will install the new OEM rad cap I bought for it. We'll see what happens from there.

 

May still have an air pocket? Let it cool and recheck level INSIDE the radiator. Other than that, the ECT could be failing due to overheated contaminated coolant. Just keep a close eye on the coolant level. If the problem persists without coolant level drop, swap the ect!

 

What is ECT? The coolant did not look contaminated, well at least by the color or clarity. No discoloration at all. The reservoir level was back to normal, just checked. I replaced the radiator cap with the new OEM I have.

Nevermind, I just looked up ECT which is Engine Coolant Temp sensor. I thought about that as well. Does it sit just above the #1 spark plug?