Hello members,

I just recently bought a 2004 xjr, a nice black one.

Besides the (so I read) normal 100 rpms variety during warmup of the engine, I worry the coolant temperature stays very long cold, approx after 10 minutes the meter start to rise and after 20 minutes it sticks halfway the meter (that part looks normal).

My last car, a tuned volvo v70 t5r did approx 2 minutes to warm up the engine coolant (on the dashboardmeter).

I know that it could be a broken thermostat but it could also be normal to this car.

Could you nice folks tell me how long it takes for your xjr to completely have a warmed up coolant-meter?

 

Your figures seem to be too long. 10 minutes to the gauge starting to rise is far longer than my car, although mine is the V6 engine. 20 minutes to get fully warm also seems lengthy. You could have a stuck thermostat

 

Are you driving or idling during warm-up? I never let mine sit and idle. That 93 octane costs too much for that, but driving 30-60 mph warms my 05 xjr up to normal temp in less than 5 minutes. 10 minutes sounds too long but the pcm should pick up on that and set a P0128 code before long.

 

I never let it run idling to get it at working temperature, just driving it normal without using extra power until i've driven it for 25 minutes then sometimes i've got the urge to floor it for a few seconds.

Ow by the way my speedlimiter kicks in at 265 km/h on the gps (270 on dash meter).
Is that normal?

 

I think a limit of 155 mph is nornally set, certainly this is the speed always quoted on road tests of performance cars with a limiter. YOu seem to be a bit over this.

 

Well guys, problem solved,

replaced the thermostat with a new one,

the old one didn't close all the way at the first step,
that's why it took so long to warm up.

The second step of the termostat did work,
that's why it did keep the temperature eventually at the right spot.

Replacement already saves me fuel

Heats up within 3 minutes at normal driving now.

Hope this post will help somebody in the future