Ok, my bad, I read ".....get up to 232 if idling in traffic then turned the efan on.....", and 180 t-stat explains dropping to 180.

In 100+ ambient, 30-45 min in bumper-2-bumper traffic, black asphalt pavement, runnin' a/c, we've momentarily seen 230 on the ScanGauge (idiot light never flickered). Our cooling system is new and we run a 180 as well. The dinky XJ rad is mediocre at best under extreme operating conditions. 9-10 months out of the year, it works fine. U'll be hard pressed to find an all efan set-up that will move as much air thru the rad as the stock fans move.

 

I know you mentioned you already replaced the fan clutch, but you might want to verify that it is operating properly. What you're describing sounds exactly like when my fan clutch was bad. I could cruise the country roads all day with the a/c on, but the moment I got into town and started slow creeping, my temps would start to climb rapidly. Keep in mind, just because something is new doesn't mean it's working properly.

 

Excellent point regarding "new" fan clutch. At 230+, u should hear the mechanical fan "roar" when driving slow and accelerating.

 

X2. Even new puppies die sometimes.

 

I'll take it in, say it's defective, and get a new one for free at Advanced Auto. I'm beginning to think that as well, every other component on the system is new. It's not stiff when it's really hot like usual, and it's not roaring like it used to, either.