V8 Temperature Gauge problems

Hi Guys,

Sorry but my first post is going to be one asking for some help im afraid!

I have a 2004 v8 range rover which i noticed had a bit of play in the water pump last week and a very slight leak, no problem order a new pump fit it myself, sorted. I ordered the pump and while waiting for it i was driving the car and an almighty boom came from under the bonnet which turned out to be the top hose blowing off and covering the engine in coolant! i have repaired the hose (still waiting for the new pump to arrive) but ever since this happened my temperature guage has been playing up.
When i turn the ignition on weather the engine be hot or cold the guage will shoot straight up into the red. This happens even if i unplug the temp sensor on top of the water pump. If i turn the ignition on to position 2 then the guage will go up to where it should be ( i.E a quarter of the way if i have been running the engine for 10 minutes or so) but after about 3-5 seconds it shoots straight up to the red. I am sure there must be water getting to the sensor as, like i said,. for the first 2 seconds the guage will read correctly.
I see a few other people have had this issue but none have posted how they resolved it. Any help will be greatly appreciated as i dont want to just throw new parts at it.

Much appreciated, Werz

Check the under bonnet fuse box for water ingress and signs/smells of burning, otherwise it's look at connectors wiring etc for damage.

First off get it scanned and look for for " activation map cooling" error. This is the heater circuit in the thermostat failed. This can lead to the thermostat leeching coolant into the wiring loom that leads direct to the ecu and deposits water just In the right place to upset the temperature gauge. On second thoughts, just go straight to the ecu and check for water / coolant in the plugs.

when you change the pump you have to change the electric thermostat.they are a major issue on the m62 engine. i do advise waiting till you done the pump before driving car again. its not a bad job changing the pump. i done mine in 3 hours.