LCR erratic coolant temperature

[Double-6s]

Hi

I noticed yesterday that my coolant temp gauge seems to be all over the place.

I let it warm up with gentle driving and wait until it hits 90 degrees. By that time I'm on the motorway so I speed up to 70+ and all of a sudden the coolant temp shows about 65 degrees or so. It then climbed back up to 90 and was steady as a rock.

It repeated this once more and then sat at 90 all the way.

Any idea what that's all about?

Car has a FMIC fitted if that makes any difference.

Any thoughts much appreciated.

Thanks

Will

 

[csd_19]

Your thermostat is knackered and needs replaced - easy enough DIY job though.

Have a search on here for thermostat replacement, good few guides and advice kicking about


*edit*

did a quick search and this thread popped up, good guide in there

http://www.seatcupra.net/forums/showthread.php?t=348098&highlight=thermostat

 

[Double-6s]

Thanks mate. What's a new thermo cost roughly? I'm guessing a hell of a lot less than on my previous car!

 

[Double-6s]

Not a lot it seems!

 

[LEE69]

less than £10

 

[SubZero]

less than £10

Plus an hour labour if you wanted to take it to a garage.

 

[wayne n]

Mine does exactly the same m8.

 

[RDS1972]

Mine does exactly the same m8.

Mine too

 

[micallef]

Same

 

[csd_19]

All the posters who replied "same", have you noticed a drop in mpg? If the stat is failing and isn't keeping the engine hot enough the ecu will add fuel as it thinks it's not heating up.

 

[G2]

Have you ruled out the coolant temp sender? Very common!

 

[GJF47]

Definitely the thermostat. Mine was doing the same when I fist had it. Picked up one off Ebay for about £8 and its been fine since.

 

[wild willy]

Have you ruled out the coolant temp sender? Very common!

Agreed. The temp sender controls two circuits hence the reason for four pins. One is the dash temp coolant display the other i believe relays temp to the ecu. Check you have a green temp sender and not a black one as these were replaced.

 

[LEE69]

One is the dash temp coolant display the other i believe relays temp to the ecu.

correct

 

[adam cupra 20vt]

If you order a thermostat don't forget to order the seal as for some reason they don't come with it.