Hi all,
Another coolant leak thread.. The car was gifted to me and has a low mileage (65k). I'm keen to fix it but hoping to DIY as garage costs may outweigh the car value.

Car always had a slow coolant leak (top up every couple weeks) and as such was more water than coolant. After the recent cold spell the coolant had seemingly frozen and leak has become much worse since then, losing around 1 litre in a short journey.

I've replaced the expansion tank and cap as it was cheap and easy to rule out. I can see coolant leaking from the front undertray, drivers side near the radiator. I've attached some photos where I spotted a leak some months ago, I suspect these connect to the intercooler? Since the leak seems to run down the pipes I'm having difficulty identifying where it's coming from. Any pointers/help appreciated, thanks

Forgot to add, the leak only seems to manifest when the car is running.

Does the aircon work? All your close-up photos are showing refrigerant pipework associated with the aircon circuit, not engine coolant pipes.

 

Which engine does the car have, please?

Had another look today and appears that the major leak is coming from the bottom of the radiator towards the drivers side, so that should be a fun 5+ hours replacement job.

 

Aircon has been working ok, I suspect the photos above are a red herring/separate issue. I believe it's a 6Y2 1.2L petrol

Yeah rad replacement is quite a faff on these. 

Be careful of rusted torx head fasteners, there will be some. 

Time spent cleaning/scaping out their heads so that tools don't slip and round them off will be an excellent investment. 

There are some decent videos on YouTube about the removal of the front bumper etc to change the radiator. It's not too bad to do once you get into it.

Thanks, I'm preparing to do it within the next few weeks.

 

Putting together a list of parts for the 'while you're in there' jobs:

Radiator O-ring Seals
Coolant thermostat
Heat temperature sender connector
Coolant temperature sensor for SKODA Fabia I Hatchback (6Y2)
Thermoswitch?

 

Can anyone assist with part numbers for the above?

Have a gander at this site for your parts, might still struggle as you must also know engine code for somethings (V5C!)

https://www.lllparts.co.uk/catalogs/skoda/CZ

So, an update:

 

As I knew the radiator was leaking and since I had to use the car to commute to/from work, being unable to stand topping up coolant with 1 litre of water every trip, I decided to use some old Barr's Leak which was lay around in the garage.

This, of course, was a mistake and while it blocked the leak it also blocked the rest of the cooling system up and caused the car to overheat in short journeys.

 

I've since flushed the system a few times, replaced the radiator and the car doesn't seem to be overheating at present and the interior heating is working again.

 

Attached a photo of the old radiator which has a lot of old coolant and other junk (including the Barr's leak) around it. The new radiator wasn't a good fit but it works.

 

However the coolant is overflowing from the expansion cap. After giving it a run around I noticed the coolant will pool up in the expansion tank, drain rapidly and then gurgle through the pipes which suggests to me it's either still partially blocked or the head gasket is done.

 

When I did an earlier flush I noticed the exhaust sputtering fluid but also noticed a potential crack in the exhaust.

 

I'm thinking of giving it another flush with Irontite Thoro-flush unless someone can suggest a cheaper/better alternative?

Some daz washing powder is the best stuff to clean the cooling system.

 

are you sure it isn’t airlocked?

 

head gasket would have it overheating and a lot of pressure in the cooling system , Also while the coolant cap is removed rev it quite hard if coolant spills out the expansion bottle that’s a sure sign the head gasket has gone 

On 29/03/2023 at 22:31, Damo152003 said:

Some daz washing powder is the best stuff to clean the cooling system.

 

are you sure it isn’t airlocked?

 

head gasket would have it overheating and a lot of pressure in the cooling system , Also while the coolant cap is removed rev it quite hard if coolant spills out the expansion bottle that’s a sure sign the head gasket has gone 

 

After replacing the coolant I ran it with the cap off until it was warm to let out any air, it kept overflowing out the top of the expansion tank until turned off.

 

I was wrong before, the car is still overheating, it didn't over heat when the cap was slightly loose and was overflowing. This started after using the radiator sealant but I haven't ruled out the head gasket yet.

One of the first steps I took was replacing the expansion tank & cap but I'm tempted to put back the original to rule out the replica stuff being bad.

HGF, everything else is denial I'm afraid.

If you take it a local garage they can do a sniff test to confirm it’s the head gasket or buy one yourself cheap enough and easy to use 

Another issue, not sure if it's related, noticed the engine management light has come on. Pulled over and car takes longer to start.

 

Connected an OBD reader and  fault code P0342: Camshaft position sensor A circuit low bank 1 or single sensor.

Going to check the electrical connections and measure the sensor if I can.

If you're fully unlucky you've cranked it over with coolant in one or more cylinders and caused the chain to skip.

 

Take the spark plugs out and look for any such coolant on the piston crowns. Torch assisted.

34 minutes ago, BreeScooby said:

Another issue, not sure if it's related, noticed the engine management light has come on. Pulled over and car takes longer to start.

 

Connected an OBD reader and  fault code P0342: Camshaft position sensor A circuit low bank 1 or single sensor.

Going to check the electrical connections and measure the sensor if I can.

 

There's nothing wrong with the sensor, that code is telling you the timing has slipped.

 

You ran it for too long with a cooling system problem, now you've killed it I'm afraid.

Pulled the spark plug covers and while there's some old crusty white corrosion, nothing abnormal for them being 20 years old.

Also pulled the sensor and between the 3 terminals read OL or high megaohms, which suggest to me it's failed. With the ignition on the connector gets 5V on 2 pins, 3rd one appears to be ground/0V.

Cam sensor is hall effect so don't think resistance measuring will get you far.

 

 

What's a spark plug cover?

24 minutes ago, Breezy_Pete said:

Cam sensor is hall effect so don't think resistance measuring will get you far.

 

 

What's a spark plug cover?

 

I should say ignition coils, I don't have a long enough socket to reach the spark plugs.

 

I can try to test the sensor with an oscilloscope but it's going to be a pain to set up

Quick update: I tested the sensor with an oscilliscope and it output a square wave so I assumed it's working.

 

I took the car to a garage who diagnosed the water pump impeller wasn't spinning. They replaced the water pump for around £200.

 

I've only taken the car for a brief test drive but it doesn't appear to be overheating anymore and once up to temperature the water flow in the expansion tank looks much more even and stronger flow.

The engine management light has also disappeared (perhaps related to the water pump being driven by the cam belt) but I'm not sure the fault code has gone and I did notice 3 beeps when starting the engine so will continue to monitor it.

 

I consider this a lucky outcome given what happened

Great result, especially given the doom and gloom posts some of us offered you.

Thanks for all the pointers, this forum + HatBoyHarvey's videos on Youtube have helped me fix a lot of issues and keep this old but relatively low mileage car going

12 hours ago, BreeScooby said:

Thanks for all the pointers, this forum + HatBoyHarvey's videos on Youtube have helped me fix a lot of issues and keep this old but relatively low mileage car going

 

HatBoyHarvey's videos are very good. A gem of a resource for these cars.