I have a 2000 D2 with 93K. It has been slowly losing coolant and I hear what must be coolant gurgling behind the dash board when I start it cold. I took it to a Land Rover specialist who did a quick check of the engine compartment , coolant reservoir etc. He saw no visible signs of a leak and suggested there might be an internal leak. He added coolant and told me to drive it and report back if it continued to lose coolant. Several days later, the Service Engine Soon light came on. The fault codes, which were read by an ELM 327 and Torque Pro, are given the attachment). The coolant level has not gone down appreciably since then, but the gurgling dash persists. No steam coming out of the exhaust pipe. Acceleration/pick up seem a little sluggish and it running rougher than usual. The radiator was replaced less than 6 months ago and the water pump two years ago. I thought I would ask for opinions here before taking it in for an official diagnosis.

 

First off adding coolant did nothing for your system, the reason your hearing the water fall is you have air in the system you need to bleed the system before you can try and find your actual problem. it also looks like you need to replace the front 2 Co2 sensors.
But I would attach your cooling problem first.

 

That sound you hear in caused by either air in system due to you losing coolant Most important thing is to locate your leak have the car warm up good and watch the engine bay for any signs of coolant leak. If its internal then you will not see it
I had a car a while back and it kept losing coolant but I could never find the leak. Ended up it was the rad when it got hot after runing it would open a crak and the coolant just steamed out in the air. Look for signs like that all your hose connections etc

 

Do you know how to bleed the air from the cooking system?
As for the codes, you are going to need to replace both front 02 sensors to take care of those codes.
How mechanical are you?

 

You or your mechanic can do a pressure test of the cooling system, the testers are loaned by the parts stores. Pump up the system to 15 PSI and let it sit, say 30 minutes. Some leaks are hard to find. If after purging the air the bubble noise comes back, you or your mechanic can do a chemical test for exhaust gas in coolant which is a strong indicator that head gaskets are needed, or not. It is possible for a head gasket to leak external, or just into the oil. But they love the coolant system most of all. It changes color with exhaust gas in the coolant.

Bad thing about coolant leaks is that they can be sneaky, happening only when driven, etc. The heat gauge is working against you in this problem, Dad's old Buick would read a little hotter slowly every day as the coolant was lost. Rover decided we should not be bothered with this, so the gauge points at 50% from 140 - 240 degrees (roughly) and you don't know it has snuck up on you until you have taken it to the Colonel for extra crispy. Once coolant level is replenished, bubbles are gone, mark the level when cold on the reserve jug, and check it daily for several weeks.

The coolant warning light should be called the "tow me to the shop" light.

Coolant plumbing map attached

 

Where in LA are u ? i had the same issue and could help you with the coolant thing. PM me if you want...

 

Replace the Bank1 sensor 1.
Bank 1 corresponds to cylinder 1.
This is the driver's side (USA).
Replace the sensor.

Bleed the system
Unclip the coolant tank.
Raise it up.
Take the lid off of it.

Run the engine at 1,100 RPM for 10 minutes.

Then put the coolant tank lid back on.
Put the tank back where it goes - clip it in.

If the level is low, top it up.
That's it.

I don't use that stupid bleed screw in the T fitting.
Screw breaks or leaks.
Just leave that screw alone.

Note - this is my way of bleeding it.
Others swear by the bleed screw.

You will kill off all three of those codes by replacing that O2 sensor.
Why do I know this?

I had those three codes.
And, I replaced the same O2 sensor.

cleared the codes.
and they did not come back.

Good luck.

 

It's not clear to me if the O2sensor/fault codes issue is related to the coolant leak issue. I gather the coolant leak is more urgent. I will bleed the air out of the system and watch the coolant level. Last Friday I drove it for 30 mins with the ELM327/Torque Pro on and saw that the coolant temp rose to 105 degrees C , at which point I turned off the engine and have not turned it on again since. What is the upper limit of safe coolant temperatures? The coolant light has not come on to date. Thanks to all.

 

221 F is warm, 235 is too warm, 240 and up is shake and bake. Normal temp is 180-200F. At 212 F the electric fan comes on. Coolant light comes on when it is time to haul truck to the shop. By monitoring the coolant temp you can decide if repairs are making progress. Air in coolant makes water rushing in pipes sound under dash. Could be air from a generic leak. Could be exhaust gas in coolant (the chemical test will show that).

 

IF you have water sound behind the dash board, I bet you also have
a cylinder misfire on 1, 2, 7 or 8?

Suspecting headgaskets.
Mine needed them at 95,000 miles.