Fabia VRS 05 plate.

 

Before i start i don't know much about cars, bikes are my thing.

 

I've been having issues with the coolant light coming on recently, I have took it to a garage recently, they said the radiator had a leak so they replaced that. 

 

It started about a month ago, the coolant light came on weekly for 2 weeks, then more frequently which i assume was the radiator leak getting worse. After they replaced the radiator it's been fine for 2 weeks then yesterday the light came on again. I don't know if this is strange or not but if you release the pressure in the expansion chamber slowly the coolant goes back up to the normal level. Once you stop and check it you can hear the pressure pushing out slightly, this may be normal i don't know, you can also see what looks like coolant on the engine top cover and down the side of the engine bay slightly. 

 

The car temperature never goes above normal at any point, even when sat in traffic.

 

I'm hoping it's not the head gasket.

 

Give me good news please.

 

 

It's head lift from when you're spanking it a bit, I bet the expansion tank hisses to let pressure out even after the cars been sat overnight and is stone cold.

I'm sure I've read something about that. Something about head bolts needing to be torqued up? There is still some pressure in there in the morning yeah.

After my radiator was changed there was some air in the system, dropped from max to near minimum when checked cold. Not pressurized. Topped up and level of coolant has not changed in 2yrs. 

 

Did you top up to max when cold?

I've had a similar problem ever since it was cold outside.

Fixed it last weekend.

The viscosity of the coolant changes due to temperature, so a top-off seems to fix it for most as far as i've read.

In my case it didn't. So after a lot of digging a lot of people suggested the sensor in the coolant-expansion tank might be the issue.

They are prone to breaking apparently, and the cold weather doesn't really help either.

A new coolant expansion tank costs only a few quid (It comes with the sensor build in)

And is an easy task to DIY, even for people with no prior knowledge. All you need is a screw driver, thongs and bottle of coolant to put in the new tank. (Its really simple)

Unplug it (1 connector), unscrew it (2 screws). Get the hoses off (2 hoses). Drain the old coolant into a flask, bucket or container. Put in the new tank in reverse order. And top off with new coolant.

That fixed it for me.

 

To get the air out of the system. (Though it should automatically vent air with the cap off.) just start the car with the cap off, and find the lowest point of the thickest hose and squeeze it while it is in operation. This gets any residual air out.

 

Edited 13 March, 20188 yr by Xsr

1 hour ago, ZMumf said:

I'm sure I've read something about that. Something about head bolts needing to be torqued up? There is still some pressure in there in the morning yeah.

 

You can try changing the head bolts for upgraded PD150 bolts, you can do them one at a time, however it may not solve the problem if the head gasket is compromised.

Hi there sorry to but in, but does anybody know the code or the name for the 2 pin electrical cable/plug, that plugs into the coolant temperature sender?

3 hours ago, Hmmbutterscotch said:

Hi there sorry to but in, but does anybody know the code or the name for the 2 pin electrical cable/plug, that plugs into the coolant temperature sender?

 

The level sensor one on the expansion tank you mean?

Part numbers of connector (housings) are printed somewhere on each housing, if you can get close enough to read it (or phone cam a picture and then blow up on a big screen).  Usually once you have the part number of the housing you'll get hits on an ebay search for housings plus pins/socket inserts and wire seals. Maybe even connectors with pre-fitted wire tails for maximum convenience.

Edited 14 March, 20188 yr by Wino

The level sensor one should be 1j0973202

23 hours ago, TMB said:

The level sensor one should be 1j0973202

no sorry not the level sensor

The coolant temp sender 2 pin D shaped electrical connector the part number is not visible on this one 

Brutal threadjacking, you really should have started a new topic, you've buried the OP's original question.

sorry can I delete the post as not to offend