Has anyone looked at intake temp on their 4.0?
Sitting in traffic after a long run I saw 96 degrees C, or 204.8F which seems ridiculous, but a PO did fit a cone filter and remove the air box so I'm wondering if this is a reliable reading or whether there's a sensor with an issue.
At a steady 70mph I saw about 54C/130F
Ambient temp was about 80F (that's HOT, for England).

 

Sounds about right especially if someone put a cone filter on it. Intake temps are pretty high on the XJ overall. The stock airbox will get lowish temps when moving since it intakes air right behind the Driver's (passenger in England?) side headlight. If someone just hacked a cone filter on it without something to seal it off from the engine compartment you are going to see higher temps.

 

With the vehicle cold soaked key on engine off what is the temp reading? With no mods and a stock air box cruising IAT on my 96 were 140s wot temps were 120s on a 60* day. With a foil wrapped intake manifold and turbo blanket I can be under 100*f 15 psi boost and a big intercooler on a 60 degree day. Unfortunately I dont have a foil wrapped intake stock air box measurement.

 

Normal operating temp for the 4.0L is 210*F +/-. The 4.0L puts out a lot of heat and, with an open filter, it sucks in all that heat. Cooler.denser air is best. But yours seems to be doing well sitting in traffic after a long run, so you can leave it as is. I dont see anything to worry about just yet. But i would probably replace that open cone with a factory airbox anyway, just because.

 

The only time I've looked at live data on my WJ 4.0, at 70*F ambient air temp, 210*F engine temp idling with the hood open, the IAT was reading 154*F. That aluminum manifold was pulling quite a bit of heat from the exhaust manifolds. Some guys have relocated the IAT to the plastic air duct and gotten better performance. Where mine is located, I could just invert it and put it in the bottom of the plastic plenum on top of the throttle body.