Coolant Temperature Warning

[jeffb007]

Hi All!

When it is cold my coolant temperature warning light comes on, but usually goes away after restarting the car. This morning the same thing happened, but when I restarted the heater stopped working, and then after about a mile the temperature gauge shot up to the max when it normally holds steady at 90. Any ideas?

Thanks in advance!

[jeffb007]

Sorry, should have mentioned that I checked the coolant levels and these seemed to be fine, ta.

[vRSsunroof]

Might be an air lock in the system....

Like any fault on these cars, its worth finding your local Vag-Com and getting it scanned for faults.

Out of curiousity, which engine is it?

[jeffb007]

It's a 1.6 petrol, I have a VW garage up the road, wonder if they would run diags for me.

[pauldazzle]

Sounds like you have an air lock, water pump failure (common problem), or a stuck thermostat. If it's any of those VCDS/Vagcom diagnostic wont show up a problem.

[Ootohere]

Could you do with changing the Antifreeze at this point since you are going to need to be sure the system is bleed OK.

Has the Ratio been checked or the Antifreeze changed in recent years?

george

[vRSsunroof]

Sounds like you have an air lock, water pump failure (common problem), or a stuck thermostat. If it's any of those VCDS/Vagcom diagnostic wont show up a problem.

Its to irrattic for a stuck stat, They normally failsafe open so he would be staiying cold not overheating. Oh and stuck stat will throw a code.

You can test the Airlock yourself, cold engine take the cap off the coolant bottle, Start the car, And watch the fluid level, Let it get up to temp which can take a while so make sure you have someone with you to talk to and supply you tea.

if the level drops like this then you had an air lock and the cap off and the level dropping has freed it, Keep the coolant topped up, After its up to temp, Replace the cap before you turn the engine off.

[jeffb007]

It could probably do with a change to be honest, but I'll try the suggestion from vRSsunroof first otherwise I will search around for some instructions on bleeding it and try that next. Thanks for all the suggestions so far folks.

[jeffb007]

Hi all, ok I tried the above for about an hour the level never went down, in fact it kept rising and lowering (I guess expanding as it heats up then cools again) Eventually the water tank just boiled over and lots of water came out of the bottom left as well, any further ideas based on this? Thanks

[mbames]

Guessing this is the Red warning light (temperature) rather than Orange (level)?

[jeffb007]

That's correct

[vRSsunroof]

Hi all, ok I tried the above for about an hour the level never went down, in fact it kept rising and lowering (I guess expanding as it heats up then cools again) Eventually the water tank just boiled over and lots of water came out of the bottom left as well, any further ideas based on this? Thanks

yea if you dont put the cap on before you turn the engine off it 'Boils over' aswell...... did your fans kick in at all??

i really would say get it scanned.... still intresting you say it boils over.. did the Rad fans kick in??

[jeffb007]

Nope, they were going this morning when the issue first happened though

[vRSsunroof]

i would look into the stat, even though its showing signs its working it sounds like its not working correctly...

Ideally scan it with a Vag Com as that will clear up any speculation.

[07 vRS Taxi]

Sent from my LT26i using Tapatalk 2

Edited 1 November, 2012 by 07 vRS Taxi

[vRSsunroof]

Sent from my LT26i using Tapatalk 2

intresting post

[jeffb007]

Stat doesn't appear to function in hot water so new one ordered, fingers crossed

[vRSsunroof]

Old School!

[Ootohere]

You said 'hot',

was that above 80 degrees celsius hot. boiling point of water is 100 degrees celsius.

(Antifreeze boiling point is higher,

different again under pressure but not important to the test.)

george

[jeffb007]

100 degrees hot, it was a saucepan of boiling water :-)

[vRSsunroof]

Testing it old school way.... pan of water set it to boil with the stat susspended in it.... when water gets to over 80C the stat should start to open, doing this makes the action visiable and is how you are supposed to test new stats before you put them in.....

I have NEVER done this ever, but always wanted to play with one just as i like to see how things work...

[jeffb007]

Hi all, back again after replacing the Stat and coolant temp sensor. The problem now seems to be more erratic after a drive around, the temperature will shoot up but then seems to cool down again, and does this several times until it gets hot enough to throw the warning light. I have noticed that since replacing those parts I've needed to top up the coolant after it has cooled down. There are no leaks so I'm guessing air in the system?

Either way my local garage wanted £87 to run a scan :wonder: so I bought a cable myself. I ran the auto tests and these are the results. I've seen the Ross wiki but I'm hoping for a layman translation!

Wednesday,07,November,2012,10:26:08:32264

VCDS Version: Release 11.11.3

Data version: 20120401

Chassis Type: 1U - Skoda Octavia I

Scan: 01 02 03 08 15 16 17 19 22 29 35 36 37 39 46 56 76

VIN: Mileage: 113740km/70674miles

-------------------------------------------------------------------------------

Address 01: Engine Labels: 06A-906-033-AVU.lbl

Part No: 06A 906 033 BG

Component: SIMOS33 1.6l 2V 00HS4600

Coding: 00031

Shop #: WSC 31480

VCID: 65CBAF4DFF7AE71

TMBCX41U932771096 SKZ7Z0C1882909

3 Faults Found:

16555 - Fuel Trim; Bank 1

P0171 - 35-10 - System Too Lean - Intermittent

17743 - Engine Torque Monitor 2

P1335 - 35-10 - Control Limit Exceeded - Intermittent

16555 - Fuel Trim; Bank 1

P0171 - 35-10 - System Too Lean - Intermittent

Readiness: 0000 0000

-------------------------------------------------------------------------------

Address 03: ABS Brakes Labels: 1C0-907-37x-ABS.lbl

Part No: 1C0 907 379 L

Component: ABS FRONT MK60 0101

Coding: 0001025

Shop #: WSC 31480 000 00000

VCID: 336F0115512E491

No fault code found.

-------------------------------------------------------------------------------

Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl

Part No: 1C0 909 601

Component: 0F AIRBAG VW51 0008

Coding: 12358

Shop #: WSC 31480

VCID: DDBB07AD572A2F1

No fault code found.

-------------------------------------------------------------------------------

Address 17: Instruments Labels: 1U0-920-xxx-17.lbl

Part No: 1U0 920 911 B

Component: KOMBI+WEGFAHRSP VDO V10

Coding: 19413

Shop #: WSC 31480

VCID: 2E591061EA0C649

TMBCX41U932771096 SKZ7Z0C1882909

No fault code found.

-------------------------------------------------------------------------------

Address 19: CAN Gateway Labels: 6N0-909-901-19.lbl

Part No: 6N0 909 901

Component: Gateway K<->CAN 0001

Coding: 00006

Shop #: WSC 31480

VCID: F0E54E19B0B8B29

No fault code found.

-------------------------------------------------------------------------------

Address 46: Central Conv. Labels: 1C0-959-799.lbl

Part No: 1C0 959 799 B

Component: 3Y Komfortgerát HLO 0003

Coding: 00259

Shop #: WSC 31480

VCID: 36693801125C5C9

Subsystem 1 - Part No: 1U6959802D

Component: 3Y Tõrsteuer.FS KLO 0009

Subsystem 2 - Part No: 1U6959801D

Component: 3Y Tõrsteuer.BF KLO 0009

Subsystem 3 - Part No: 1U0959811D

Component: 3Y Tõrsteuer.HL KLO 0009

Subsystem 4 - Part No: 1U0959812D

Component: 3Y Tõrsteuer.HR KLO 0009

1 Fault Found:

01336 - Data Bus for Comfort System

80-00 - Single-Wire Operation

-------------------------------------------------------------------------------

Address 56: Radio Labels: 1J0-035-18x-56.lbl

Part No: 1U0 035 161 D

Component: Radio GRO 0001

Coding: 00407

Shop #: WSC 31480

VCID: 2A511C71D6E4089

1 Fault Found:

01336 - Data Bus for Comfort System

80-00 - Single-Wire Operation

End ---------------------------------------------------------------------

Edited 7 November, 2012 by jeffb007

[vRSsunroof]

Those first 3 codes pointing to the system running LEAN is pointing towards the MAF, Google the fault codes and the rosstech site says faulty MAF.

Which makes sense as if the MAF is not working correctly then the engine will over/under fuel causing it to run hot.

Best thing to do is Clear all codes, then take it for a drive. if the codes come back up then investorgate the MAF

Edited 7 November, 2012 by vRSsunroof

[jeffb007]

I cleared all the codes and took it for a spin, the error didn't come back after driving for a while. I only have the single wire ones back. Could the fact I'm not getting any hot air through the blowers be related to this, as in should the coolant be directed somewhere that it isn't going? I took temperature and maf readings while driving around, it is available here https://dl.dropbox.com/u/7012825/LOG-33-16-05-xx-xx.CSV I'm not sure if there is anything unusual in the maf readings, but the coolant temp seems to regulate itself normally for a certain amount of time and then decides to shoot up.

[Cossie1]

By the sounds of it, you either have a big air lock, faulty water pump or headgasket issues.