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Discussion Starter · #1 ·
if you have noticed this winter that you car takes a long time to reach 90oc, this is normal as its cold but when it has reached 90oc and when you start driving or go on the motorway for example, if it drops to 70-80oc etc and think its the end of the world, most likely this is your problem

You most likely have a faulty thermostat which costs 7-8quid and is easy to change. Make sure you top up with the right coolant and bleed the system properly

thank you for reading.
 

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Exactly the same issue on my 1.8T, also throws a code since the artic weather!

P1296 error in mapped cooling system (usually temp sensor or thermostat)

the above code keep popping up and i keep clearing it.

Ive purchased both as theyre cheap enough, i just havent had time to get them fitted.

will keep you folks updated on the outcome
 

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yeah i had the same problem...engine light came on too. changed the thermostat and the coolant temp sensor and it's running perfectly now!
 

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My temperature gauge never seems to get between 1/2 the normal place for it to rest (90c) sometimes. Rarely it gets to the 90c
Same here! I have a 1.4 and before the cold weather the car temp was working fine always going to 90c, but ever since the cold snap has come it its always been less that 1/2 the normal place max.

I've had the car running stationary a few times and its heated up to 90c fine but once i hit the motorway it drops right down to the bottom.

Do I need a new thermostat? I only recently get a coolant change with g12+ so dont want to bleed the system again!
 

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Is this the new better thermostat with new oring?

Part Number: VTS261£10.97
Engine Details: 16Valves, 75 bhp
Engine Number/Code: AHW
Cam Type: DOHC

 

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Discussion Starter · #8 ·
My temperature gauge never seems to get between 1/2 the normal place for it to rest (90c) sometimes. Rarely it gets to the 90c
Same here! I have a 1.4 and before the cold weather the car temp was working fine always going to 90c, but ever since the cold snap has come it its always been less that 1/2 the normal place max.

I've had the car running stationary a few times and its heated up to 90c fine but once i hit the motorway it drops right down to the bottom.

Do I need a new thermostat? I only recently get a coolant change with g12+ so dont want to bleed the system again!
yes a new thermostat should sort it out. There is a tap which you could drain and use the coolant so you dont need to buy new one
 

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Discussion Starter · #10 ·
on your right is the top radiator pipe, underneath that is the bottom radiator pipe iirc and it will be screwed with two 10mm bolt onto the side of the engine iirc. it should have a plastic outer casing
 

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I had a lot of trouble finding the thermostat. Its very hard to see and find... on the right hand side (when viewing from front)/passenger side/near side of the engine block is where the thermostat on a 1.4 is located. I will try finding or taking a picture but won't be able to till Monday or Tuesday.
 

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i thought when the gauge doesn't hit 90c, it doesn't neccessarily mean there is a fault on the car... mines done it on both golfs, and both run fine
 

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Discussion Starter · #14 ·
i thought when the gauge doesn't hit 90c, it doesn't neccessarily mean there is a fault on the car... mines done it on both golfs, and both run fine
the car will run fine but it will be using more petrol than it should. once you drive the car and it is fully warm, it should stay solid at 90oc +- a few degrees. most likely your thermostat probably need replacing too. very common on golfs and only really noticeable in the winter when the cool air is enough for the car to stay cool.
 

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Discussion Starter · #16 ·
if you did remove the thermostat and replaced it, you should use a new o ring and did you make sure that the o ring was actually put in the right order, should be the thermostat into the block and then the o ring and the black housing on top. i did my o ring first and then thermostat and the temperature was fluctuating and then i fixed it and it was fine
 

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chaps change thermostats if you want but i would not hold out for it curing the fault listed by the op

its simple the car is struggling to reach operating temp due to the cold as the ambient temp is just too low, and you are using more fuel due to the air being dense which =more fuel-which is a fact.

I had a chap come in my garage a few weeks ago with the op related problems and insisted a fitted a new thermosat for him as he had been reading the FACTUAL internet, i insisted this may not help, but i did it, and sent him on his way with the same issue [:p]
 

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Discussion Starter · #18 ·
i know a thermostat may not help my problem but a thermostat would help someone who has a fluctuating temperature. by that i mean it will reach 90oc when in traffic but when starting to move say on the motorway the needle will drop

I changed the thermostat because i didnt know if mine had been changed before so i just replaced it as i have done a few other service things on the car and for the sake of 7quid i thought i might aswell change it.
 

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i know a thermostat may not help my problem but a thermostat would help someone who has a fluctuating temperature. by that i mean it will reach 90oc when in traffic but when starting to move say on the motorway the needle will drop

I changed the thermostat because i didnt know if mine had been changed before so i just replaced it as i have done a few other service things on the car and for the sake of 7quid i thought i might aswell change it.
Doubt it.

Think of driving in a queue where you are stood still there is little air going to the radiator to keep it cool. When driving doing 70mph, air thats something like -4c is getting rammed into the radiator keeping it very cold.
 

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a thermostat would help someone who has a fluctuating temperature. by that i mean it will reach 90oc when in traffic but when starting to move say on the motorway the needle will drop.
Mine does this exactly but didnt realise it was a problem, Will definitely look into changing mine soon. Im not sure what to buy exactly though? To replace the old one will i have to buy a new o ring aswell and this?

A pic of its location will be great for when I do end up changing it.
 
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