Help! flashing water light and erratic temp gauge...

[amazingdave]

Hello,

Last night when I stopped the van I heard gurgling from the rad. so I thought top up the coolant and bleed, which I did, It took about 1litre (into the sealed system).

then this morning on the way to work the red light started flashing and the temp gauge showed zero for most of the journey, I stupidly imagined I must have disturbed the wiring so didn't stop. then towards the end of the journey the temp gauge shot up to off the scale then dropped to normal then off the scale again, then down to nothing repeatedly but fairly randomly. when I stopped the van the water was still full but the engine is making a bit of a "rattle" towards the left hand side looking forwards. water pump? or more serious? and how do I find out?

What the blazes is going on?

ta

[DiscoDave]

if it is beeing erratic it could be that there is air in the system, as water is pumped round and the air could be moved to the temp sensor (gives reading or low temp) then water comes (gives high reading)!! just a thought!

[kevtherev]

I agree with dave here ,follow the proceedure in haynes or on the wiki about bleeding the system