I understand that the temp gauge on my 98 / Xk8 is a "dummy gauge". From what I've read, it should always be dead center.
The past few days, I've noticed the gauge has moved up no more than a 64th of an inch past dead center. But never the less, not centered.

Your thoughts?

 

[QUOTE=Anthony8858;1524420]I understand that the temp gauge on my 98 / Xk8 is a "dummy gauge". From what I've read, it should always be dead center. The past few days, I've noticed the gauge has moved up no more than a 64th of an inch past dead center. But never the less, not centered.

Your thoughts?

It does operate like the standard Ford, and other car manufacturers temperature gauges in that it goes to dead center and stays there with little to no fluctuation. The problem with this gauge, is that it gives you little warning before it pegs to red-line possibly causing catastrophic engine damage. A forum member has come up with a solution, do a search for 'RealGauge'. This conversion allows the factory temperature gauge to display temperature data in real-time. If you have the three gauge set-up, and not the factory Navigation, he also makes a harness that will allow the factory oil gauge to display real-time data as well. I believe he sells conversion kits to convert the factory Navigation to the Three Gauge set-up, (not sure on this), or the components can be sourced from this site and links provided in posts by members who have done this conversion.

I just noticed the same thing happening on my XKR this Summer, with the 64th of an inch rise on the gauge over dead center. Not quite enough to put the pointer completely above of, or off of, the dead center line, but definitely above where I am used to seeing it sit at dead center. When I have been driving it hard, the pointer sits at the center line, but may creep up slightly after exiting the highway, but not enough to be fully outside, or above the center line. When driving around town at normal speeds the pointer usually sits at a 64th of an inch below the center line, but not fully outside of the center line.

Also the fans were coming on after a few miles of driving around town with it being 70*F outside. I got a new Reservoir Cap overnight from NAPA for $15.78, and installed it the next evening. Now the fans do not start running after a few miles, and actually slow down, speed up, and stop when idling at stop lights. The old cap looked fine, but I noticed a slight residue around the bottom rim when I unscrewed it to check the coolant, due to the fans running more than usual. I did not know until I got the new cap, that the core of the old cap no longer spun freely, I did not know it was supposed to spin at all, and I was replacing it due to the leakage, and the flattened O-Rings I had noticed when I took it off and figured it was no longer sealing properly. Also, the last couple of times I took the cap off, on the same day, it became very hard to tighten down completely to seal all of a sudden, and took adjustable pliers to unscrew. I checked and it was not cross threaded, it just gave up and would no longer budge. The new cap screwed right on with no problems, and comes off with no problems, as I have been checking the coolant level after burping out some air that must have gotten in through the old cap, other than that I have had no problems.

Suggest you take a look at the Coolant Reservoir Cap for flattened out O-Rings, and possible leakage around the bottom rim of the cap, and whether or not it has become hard to remove. Either way I would get a new one, they are cheap, and you can get it overnight if you have a NAPA close to you, since your symptoms are exactly what mine were a few days ago. It has been over 101*F here lately, and I have had no cooling issues whatsoever, good luck.

 

I'm one of the few Jag owners that does not have a smart phone of some sort. If you do, you can download the torque app, buy a OBD wireless adapter and read the actual temp.

 

I just purchased the torque pro app $5.00 and a bluetooth 0BD II adapter on amazon $8.99. It is awesome !!! It will give you a lot of information, it is a must have device for Jag enthusiasts!

 

How is the adapter hooked up to the car?

 

Does anyone know WHY it's designed like this? It seems to be accurately measuring engine temperature up until the midpoint. Why does it stop being functional at that point?? I didn't realize that this was common among other cars - it seems stupid.

 

The OBDII to Bluetooth converter plugs into the data port located just above the hood/bonnet release handle. The Torque app provides a lot more info than a standard code reader.

 

Because some consumers get nervous when they see normal temperature fluctuations and visit the dealer unnecessarily during the warranty period, costing the manufacturer money.

Here is the link for RealGauge for those who are interested: http://www.thejagwrangler.com/xk8--x...realgauge.html. RealGauge also has an audible alarm for both coolant temperature and oil pressure, so if you begin to overheat or lose oil pressure you can pull over as quickly as possible and shut off the engine.

 

HI,

When I ordered my reader there were many to choose from and I had read that not all readers work with all cars. I read a post here where someone said to get the older fifmware for the Jags, version 1.5 I believe.

This is a link to the one I bought which seems to work very well. I havent had time to use all of the functions but the temp guage, throttle position, rpm , vac,
etc work really well in real time.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

 

PS I left it plugged in last night and the car fired right up this morning so I think it might sleep when the vehicle isnt running or just have a tiny current draw.

 

03 XKR gave you good advice regarding replacing your coolant expansion tank cap as a first step. They do indeed fail over time. When they get very difficult to unscrew, you can bet you need a new one....

 

Exactly. Oil pressure and voltage gauges fall under the same category. Most consumers are not car savvy enough to know what's normal and what's not.

 

On the later X150 version there are no oil or temperature gauges at all.