Thread: Heater matrix

There's no easy way to get the matrix out. It's part #1 & the car is built around it .

It might be easier to pressure test the cooling system & use a torch to check the matrix from the drivers footwell area. Any leak will soon be apparent, especialy if it's big enough to mist out of the vents.

To come out of the vents, it sounds like a pin hole leak spraying out under pressure, which is making it's way into the air ducting via the fans.
If you have a look under the drivers side dash, do you have damp carpet or signs coolant dripping down the side of the tunnel?
It's pretty easy to remove the panels under the steering column and the panels on the side of the console which *may* give you some visual clues as to what is going on.
You may be able to get in there with a torch with the engine running and see evidence of coolant spraying out.
There should be some evidence if it is a leaky heater core.
I recently used a procuct called liquid intellegence 245, which fixed my leaking heater core. Might be worth a shot before tackling the heater core replacement job.
There are shortcuts to replacing the heater core, so you won't have to remove the entire dash as directed in the shop manual proceedure.
Some great info here: Heater Core Replacement (Range Rover 4.0/4.6/P48)

That's great advice guys, thanks! So far I have already removed the panels under the steering column, the glove box and the radio, a/c controls and the switch panel and have been working my way in as I thought that maybe I would have to remove 90% of the dash to get to it as it does seem to be the least accessible part of the car!
I have had coolant dripping onto the transmission tunnel on the drivers side footwell and had hoped that it wouldn't get too bad but it seems it has gone from a leak to a flow into the footwell. I have not run the car since as I have assumed that the leak is fatal so got stuck in and have had concerned about it overheating but this is easy to control and monitor at tickover on the driveway as opposed to the highway. There shouldn't be any problems with reaching operating temperature quickly as it is 32degrees here at the moment. I haven't pressure tested the system and that is not something I have ever done so I am not sure how to go about it but I will research it and do that if I cannot see any leaks when it's running.
I may top up the car this morning with coolant and see it it leaks into the footwell again.

I have similar issues on the odd occasion and rather than having any spray have had steam vapour coming out around the dash after 5 minutes of starting the car from cold. Only lasts a minute or two when it does occur and have also drips coming down occassionly in the rest pedal to the left of the brake. I thought this was an heater o ring issue and watch my cooling fluid reserve all the time but hardly uses any water anyway. Are you sure your steam is coming from the vents and is not the orings at fault.

It definately came from the vents. It was like someone had switched on a dry ice machine and the car filled with steam accompanied by a loud hissing noice and preceeded by a 'pop' which i thought may have been the matrix failing.

I just topped up the coolant and ran the car up to normal temperature and had steam escaping up by the instrument binnacle.

Not good

Bugger... I think you have no option left other than to remove the dash and inspect the heater matrix.

I haven't done a write up of how to do it, but did take a lot of photos when I removed the dash to replace my heater core o-rings. Photos are at Heater O-Rings

Best wishes, Paul.