Seat Leon FR Estate Mk3 2015 - Coolant Loss/No driver side heat

[JCK142]

Hi All,

I was hoping I could get some advice from others who have maybe experienced a similar issue.

I noticed last winter that my drivers side vents weren't receiving much heat compared with the passengers. Did some research and worked out its probably the heater matrix thats blocked. I left it for now and decided ill address it later in the year as weather perked up.

Then last month I got a notification of low coolant level on the dash, so I checked the reservoir and it was below minimum. I topped it up and it ran for a week before throwing up the low coolant alarm again. I checked the engine bay for any visible signs of leaks and saw nothing, so topped it up and waited. It then ran for a good 3 weeks before coming up again. I had it in the garage in this time and the also found no visible signs of leaks.

Now I'm thinking to replace the heater matrix anyway, but I'm wondering if its possible this could create the loss of coolant also. Is there anything else I should be looking out for? I'm going to attempt to replace the heater matrix myself as videos on here seem doable and I don't fancy paying £250.

Thanks in advance for your help!

Jack

 

[Leon2014]

Hi All,

I was hoping I could get some advice from others who have maybe experienced a similar issue.

I noticed last winter that my drivers side vents weren't receiving much heat compared with the passengers. Did some research and worked out its probably the heater matrix thats blocked. I left it for now and decided ill address it later in the year as weather perked up.

Then last month I got a notification of low coolant level on the dash, so I checked the reservoir and it was below minimum. I topped it up and it ran for a week before throwing up the low coolant alarm again. I checked the engine bay for any visible signs of leaks and saw nothing, so topped it up and waited. It then ran for a good 3 weeks before coming up again. I had it in the garage in this time and the also found no visible signs of leaks.

Now I'm thinking to replace the heater matrix anyway, but I'm wondering if its possible this could create the loss of coolant also. Is there anything else I should be looking out for? I'm going to attempt to replace the heater matrix myself as videos on here seem doable and I don't fancy paying £250.

Thanks in advance for your help!

Jack

Hi,
I had the same issue. I removed both hoses off the heater matrix in the engine bay and used a hose to flush the matrix. The heat in the vents came back. I removed the metal banded type hose clips and replaced these with jubilee clips. I have repeated this around every 6 months instead of waiting for it to go wrong.
I currently have another coolant issue with it disappearing, with no sign of where it has gone. A mechanic pal is going to try and see if he can see any evidence of where it is going this week. It must be leaking and getting burnt off somewhere.

 

[SRGTD]

Hi All,

I was hoping I could get some advice from others who have maybe experienced a similar issue.

I noticed last winter that my drivers side vents weren't receiving much heat compared with the passengers. Did some research and worked out its probably the heater matrix thats blocked. I left it for now and decided ill address it later in the year as weather perked up.

Then last month I got a notification of low coolant level on the dash, so I checked the reservoir and it was below minimum. I topped it up and it ran for a week before throwing up the low coolant alarm again. I checked the engine bay for any visible signs of leaks and saw nothing, so topped it up and waited. It then ran for a good 3 weeks before coming up again. I had it in the garage in this time and the also found no visible signs of leaks.

Now I'm thinking to replace the heater matrix anyway, but I'm wondering if its possible this could create the loss of coolant also. Is there anything else I should be looking out for? I'm going to attempt to replace the heater matrix myself as videos on here seem doable and I don't fancy paying £250.

Thanks in advance for your help!

Jack

I’m guessing your car’s a diesel?

Check out post #2 in the discussion topic at the link below;

Seat Leon 2.0 TDI coolant loss

Hi, I have a 64 plate Leon FR 2.0 TDI (184). My coolant seems to disappear to which several mechanics have had a look, however recently I have also had a low engine oil light appear. They’ve pressure tested the expansion tank to which it’s held pressure. They have done the fluid dye test...

www.seatcupra.net

 

[nanobis]

Hi,
I had the same issue. I removed both hoses off the heater matrix in the engine bay and used a hose to flush the matrix. The heat in the vents came back. I removed the metal banded type hose clips and replaced these with jubilee clips. I have repeated this around every 6 months instead of waiting for it to go wrong.
I currently have another coolant issue with it disappearing, with no sign of where it has gone. A mechanic pal is going to try and see if he can see any evidence of where it is going this week. It must be leaking and getting burnt off somewhere.

I've similar issue with loss of coolant. I thought I solved the issue with the billet coolant vent from 034motor sport, but it keeps loosing coolant.

Slow Occasional Coolant loss over 5 month, some questions.

I've posted this a comment on different thread but didn't want to distract had a few extra thoughts on it. I've a 2016 1.8tsi FR DSG Estate on 68k. I'm noticing that I'm loosing a bit of coolant over time. I bought the car June from a as a part ex from a PSA/Vauxhall/KGM (Non VAG) dealership...

www.seatcupra.net

I've the 1.8 TSI Fr.

 

[MartinThorn]

Hi,
I had the same issue. I removed both hoses off the heater matrix in the engine bay and used a hose to flush the matrix. The heat in the vents came back. I removed the metal banded type hose clips and replaced these with jubilee clips. I have repeated this around every 6 months instead of waiting for it to go wrong.
I currently have another coolant issue with it disappearing, with no sign of where it has gone. A mechanic pal is going to try and see if he can see any evidence of where it is going this week. It must be leaking and getting burnt off somewhere.

Yes, it sounds like the usual heater matrix problem, especially if it's a diesel TDi - matrix blockage causes coolant overheating during the dpf regen cycle which causes loss of coolant in sudden surges (only when the regen cycle occurs - not a leak as such, it just boils out of the expansion tank).

I had exactly the same problem and changed the matrix (and all the coolant) myself - medium level complexity job for DIYer, mainly due to the annoying access to the matrix. This dismantling to get to it is also why it costs quite a lot at dealers even though the matrix itself is only about £70 or so (depending upon which one you get).

Here's when I replaced mine:

https://www.seatcupra.net/forums/th...ems-but-sorted-in-the-end.476713/post-5062086