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Model specific boards => Golf mk2 => Topic started by: Goops on 28 November 2007, 23:07

Title: Water temp light..normal?
Post by: Goops on 28 November 2007, 23:07
Hi,

I noticed this week when my engine temp reaches near the 114 mark - the coolant light comes on (water temp too high warning?) the fan comes on and the light goes out. I checked and coolant level is ok.  :huh:

I would have asummed this was normal but it never used to happen before, only used to come on when the coolant was low?

Apologies in advance for what may be an eternally asked question!

Thanks in advance,

Goops
Title: Re: Water temp light..normal?
Post by: Leon R on 28 November 2007, 23:20
My valver went up to 116 in summer, in traffic but the light never came on. What was your water temp guage reading at that time?
Title: Re: Water temp light..normal?
Post by: Goops on 28 November 2007, 23:25
Water temp gauge was sitting near halfway?
Title: Re: Water temp light..normal?
Post by: OakeyDoak16v on 28 November 2007, 23:28
Mine is usually about 100 on a normal drive and can get up to 110 through town. Is that normal? How do you know?
Title: Re: Water temp light..normal?
Post by: Goops on 28 November 2007, 23:37
My query is regarding the coolant warning light....is it normal for it to come on at halfway mark on water temp gauge?  :huh:

"Normal" engine oil working temp as far as i know is between 100 and 120....
Title: Re: Water temp light..normal?
Post by: OakeyDoak16v on 28 November 2007, 23:46
Sorry not sure but would check the resevoir if it was me. I have been wondering about my engine temp lately and think it best to do a flush and replace with new coolant for the winter. The only thing i know about coolant is not to mix different types together as can cause problems. That's still not answered your question though.
Title: Re: Water temp light..normal?
Post by: Goops on 28 November 2007, 23:56
Coolant level is fine, flush done not long ago (doubt its dirty sensor), got G12 coolant with water only!
Look forward to all your comments, otherwise il have the NFS....nervous fidgety syndrome of checking whether the red light has pinged or not! :laugh:

G
Title: Re: Water temp light..normal?
Post by: OakeyDoak16v on 29 November 2007, 00:01
Just a thought.. What if your thermostat isn't kicking in when it should do? Probably shouldn't worry till you get steam comming out of your engine.
Title: Re: Water temp light..normal?
Post by: gibby on 29 November 2007, 07:44
Normal oil running temp is safe up to something like 140 on the MFA according to the handbook. Valvers run hotter too. As for the water temp light, if oil temp is ok and the gauge is not going to the red and the level is not below minimum then you should be ok. If it's the thermostat sticking then the water temp would go higher than it usually does but not to the red line. Half way is normal. There's a way of checking if it's your thermostat's ok by waiting for it to get to temp and then checking your bottom hose to see if that's warm because if it's up to temp but bottom hose is cool then thermostat is probably sticking, but do a search just to confirm if that's correct. 

My water light flickers on on my Rallye sometimes but I find a quick slap on the top of the dash stops it. :rolleyes:
Title: Re: Water temp light..normal?
Post by: OakeyDoak16v on 29 November 2007, 08:37
If in doubt, give it a clought!! :laugh:
Title: Re: Water temp light..normal?
Post by: rubjonny on 29 November 2007, 13:14
check the level when the light comes on, it may be dropping due to pressure building up in the tank?
Title: Re: Water temp light..normal?
Post by: Goops on 29 November 2007, 13:49
Thanks, I wil try that.....however I dont want to open the coolant tank cap at these temperatures?
(My tank plastic casing is kinda dull and cant see the levels from there)

Thanks for all your comments  :smiley:
Title: Re: Water temp light..normal?
Post by: rubjonny on 29 November 2007, 13:53
no definitly not!  shake the car, that sometimes allows you to see the levels when you see the slightly murkier water sloshing about in the murky tank  :grin:
Title: Re: Water temp light..normal?
Post by: Goops on 29 November 2007, 14:09
 :laugh: Sounds like a practical solution will try this at some point tommorow!
Say I did notice a level drop due to pressure build up in tank....what would be the way of releasing this?
Refill, let engine run and wait to boil over then cap back on?

Thanks!
Title: Re: Water temp light..normal?
Post by: rubjonny on 29 November 2007, 14:55
nah just top it up a wee bit more, also id replace the tank cap in case its venting too soon/late :)
Title: Re: Water temp light..normal?
Post by: Goops on 29 November 2007, 15:59
Thanks Il top up tonight! I did actually get a new cap from VW last month..touch wood it didnt come on today so will find out on the way back from work today!
Title: Re: Water temp light..normal?
Post by: rubjonny on 29 November 2007, 16:06
coolio :)
could just be the tank sensor is covered in crud so not working well, if you cant see thru the tank then a good chance this is so!  New one isnt too much :)
Title: Re: Water temp light..normal?
Post by: monkeyalan on 29 November 2007, 17:29
Normal oil running temp is safe up to something like 140 on the MFA according to the handbook. Valvers run hotter too. 

is that right!
mine went to about 116 once and i nearly shat myself as it normally never goes above 102 - 104.
Title: Re: Water temp light..normal?
Post by: gibby on 29 November 2007, 17:39
Yup, it said it in my handbook on my old 8v cabby. I've seen my old 8v cabby up to 116 while tanking down the M1 and that was ok. I hold my camper off when it gets to an oil temp of about 120 so you should be ok in yours. 116 should be ok but if it starts getting to 120+ then I'd personally slow down.
Title: Re: Water temp light..normal?
Post by: monkeyalan on 29 November 2007, 17:42
it was in the middle of Buxton on a Saturday afternoon this summer.
I just pulled over and let it cool down.
My car was new then and i was a bit paranoid i guess.  :grin:
Title: Re: Water temp light..normal?
Post by: bobbymk11 on 29 November 2007, 19:20
my old valver used to be 95 upto 115 depends on driving style

my current 8v ...on motorway sits about 88-90...in heavy traffic can creap upto about 100-105....seems to keep its self cooler than a valver..but has had engine re-build so maybe thats helping...as like new

Title: Re: Water temp light..normal?
Post by: Goops on 30 November 2007, 00:20
Thanks Rubjonny and all,

if anyone was on the m25 today after 6pm, it was a valvers nightmare!! Drove 30miles in 1st and 2nd gear looking at the oil temp light every now and then! The water temp light flashed when i hit 114 engine oil temp, flashed for a few seconds then didnt come on again (sounds like im describing a UFO sighting i know).. :grin:

Man was I happy to see the m4, cruised and let the car cool down nice with the air flow  :cool:
Title: Re: Water temp light..normal?
Post by: CHRIS_MC on 30 November 2007, 00:28
whether or not its relevant, my coolant was getting red hot and boiling, it turned out to be my head gasket, cost me a bit to have the head reskimmed and my valves re-cut
Title: Re: Water temp light..normal?
Post by: rubjonny on 30 November 2007, 09:30
hmm, sounds more like the temp sensor is starting to go faulty, or the clocks!  If the clocks detect a low water condition, the light wont go off untill you stop the engine then start it again.  It might be your sensor has an intermittant internal short, or the wiring is earthing somewhere.  If the sensor or wire shorts this causes the light to flash and the needle to slowly rise to the max line, if the short only happens briefly it might not be enough to make the needle move a noticable ammount.

I'd start with checking the wiring along its length for damage, and if that checks out replace the sendor with another from the local scrappy :)
Title: Re: Water temp light..normal?
Post by: Goops on 30 November 2007, 16:16
Thanks, Touchwood seems ok so far!  I understand the temp sensor/sender is inside the tank right? Is this reachable/changeable or would I look at simply replacing the whole tank? Will check the wires tommorow, apparently we have a rain free weekend! Might even give her a wash/wax for the placebo effect!  :smiley:
Title: Re: Water temp light..normal?
Post by: rubjonny on 30 November 2007, 16:34
the one in the tank is the level sender, the coolant temp sender is in the plastic flange on the front of the block, the black one :)
Title: Re: Water temp light..normal?
Post by: Goops on 30 November 2007, 17:38
aha!  :grin:

Cheers, will check this out tommorow! Have a fantastic weekend  :smiley:
Title: Re: Water temp light..normal?
Post by: Bob Hewitt on 30 November 2007, 18:00
i've had this problem with both my current 8 valve gti's. on my '89 it was a faulty sensor - causing the red light to come on for no apparent reason (both water and oil temp ok). you could switch off the engine - and it would be fine when you started up again straight afterwards.
i've just started running a '90 gti as well - and today on an 80 mile round trip, when the oil temperature got to 102 degrees - the water temperature light strats to flicker!
now here's the strange part - on my '89, the water temp needle is bang in the middle - and never overheats - but is slow to warm up.
the '90 warms up quickly - but the needle is never more than up to the 1/4 mark (i've never seen this on a mk2 gti).
i spoke with the guys at wilsons of rhuddlan north wales - who have looked after my golfs for the past 20 years - and they said it was ok.
there will always be the odd faulty/sticky guage and sensor - or dodgy warning light - don't worry too much if the car is running ok - and shows no other problem signs.
Title: Re: Water temp light..normal?
Post by: rubjonny on 30 November 2007, 18:03
whats the oil temp like on the one which only gets up to 1/4, could be a stuck open/missing thermostat?  Could just be an under-reading sender as well of course.
Title: Re: Water temp light..normal?
Post by: Bob Hewitt on 30 November 2007, 18:18
before i had it serviced (this last week) the oil temp was running at 98 - but after the service it's higher - regularly at 100 and up to 106.
when i bought the car (ebay middle of november) the heater was not existant - and the guage never above 1/4 mark.
wilsons did a full service and safety check for me - and bryn (the mechanic who usually works on my cars) fixed up the heater for me (needed a good flush through the matrix etc). he said not to worry unduly about the guage - and the 'stat was ok.
i must admit, i'm really funny (read fanatical) about everything being right on my gti's - and we're now in the (sad?) position of having 'his ' n hers' 8v mk2 gti's - with my daughter running a mk3 (just washed my mouth out) 16v.
i still have my '87 broken for spares (when the engine expired) - and will always own/run a mk2 as long as i draw breath.
my tornado red '89 has covered 240,000 - and is as much a pleasure to drive now as ever.
the (newly aquired) '90 has 144,000 (but no power steering!!) and is very tidy- i'll try and post some pictures when the weather picks up.
Title: Re: Water temp light..normal?
Post by: rubjonny on 30 November 2007, 18:24
oil temp sounds perfect to me, id say its just the sender or gauge under-reading :)
Title: Re: Water temp light..normal?
Post by: Bob Hewitt on 30 November 2007, 18:42
ok - thanks for the help on that one. i'll have a look myself over the weekend - as it's going to drive me mad eventually!!
Title: Re: Water temp light..normal?
Post by: Goops on 10 December 2007, 17:09
Just an update...
stopped by mechanics and mentioned the coolant light etc...
he definitely reckons its the sensor or the clocks, getting a new tank with sensor....
any opinions on the GSF one?

Think i might jus fork out the extra 20ish quid and go for the VW dealers!

Thanks,
G
Title: Re: Water temp light..normal?
Post by: rubjonny on 10 December 2007, 17:24
unplug the level sensor plug, and put a piece of wire between the pins.  if the light stops flashing its the level sensor, if it doesnt then its not the level sensor ;)
Title: Re: Water temp light..normal?
Post by: JimR on 10 December 2007, 18:54
i've had this problem with both my current 8 valve gti's. on my '89 it was a faulty sensor - causing the red light to come on for no apparent reason (both water and oil temp ok). you could switch off the engine - and it would be fine when you started up again straight afterwards.
i've just started running a '90 gti as well - and today on an 80 mile round trip, when the oil temperature got to 102 degrees - the water temperature light strats to flicker!
now here's the strange part - on my '89, the water temp needle is bang in the middle - and never overheats - but is slow to warm up.
the '90 warms up quickly - but the needle is never more than up to the 1/4 mark (i've never seen this on a mk2 gti).
i spoke with the guys at wilsons of rhuddlan north wales - who have looked after my golfs for the past 20 years - and they said it was ok.
there will always be the odd faulty/sticky guage and sensor - or dodgy warning light - don't worry too much if the car is running ok - and shows no other problem signs.

As an aside to this, my 8v 90 spec coolant temp never goes above 1/4 either, unless in traffic where you might see 2/3, fan never comes on either way so may check/replace fan switch and temp sender before too long just incase. Oil temp doesn't work on the mfa but i think its the sender in the oil filter housing, just nee to earth it to the block to see if i get any reading from it.
Title: Re: Water temp light..normal?
Post by: rubjonny on 10 December 2007, 21:39
sounds like the thermostat is missing or stuck open, possibly this was done to work around a dead radiator switch problem...
Title: Re: Water temp light..normal?....update
Post by: Goops on 19 January 2008, 17:25
I know this is kinda old but thought I would update on the temp light thing..

Today,I finaly changed the water tank with new one from VW, was driving for an hour and behold the light came on.
So, it is definitely not the level sender! :angry:
Next step, change the coolant temp sender?

The car is not overheating etc so I am hoping it is ok to drive etc as per norm?

Thanks in advance,
Goops
Title: Re: Water temp light..normal?
Post by: rubjonny on 19 January 2008, 17:36
put a wire between the pins of the level sender plug, if it stops flashing you know its that :)
Title: Re: Water temp light..normal?
Post by: Goops on 21 January 2008, 18:37
Thanks John,

It deffo is not the level sender, have you got a diagram/photo of where to locate the temp sender on the actual block?
I am guessing it will be a pain to remove due to corrosion etc!

Alternatively, I  can choose to ignore the light as long as water temp gauge and coolant levels are fine. Then get the sender changed when I do the gas flowed head and 2.0l conversion!?   :laugh:

Thanks for the patience btw  :wink:

G

Title: Re: Water temp light..normal?
Post by: rubjonny on 22 January 2008, 10:42
if ya looky on the side of the head, there are 3 small single pin sensors.  All 3 are the same type/rating, the one for the gauge is the re/yellow one.  If you warm up the engine then swap the red/yellow wire to each of the 3 sensors, check the gauge reading and if any change significantly you found yourself a faulty one :)
Title: Re: Water temp light..normal?
Post by: Goops on 22 January 2008, 22:21
Thanks John,

I will try this on the weekend, dark when I leave for work and when I return home! :angry:
Any ideas on costs of these senders from the dealers?

Thanks!
Title: Re: Water temp light..normal?
Post by: rubjonny on 23 January 2008, 10:55
049 919 501 - 22.80+VAT :)
Title: Re: Water temp light..normal?
Post by: Goops on 27 January 2008, 16:43
Update:

Swapped the red/brown wire round on the sensors (except for the one to the Warm up regulator)...
I got the same/normal readings and as usual the red light came on when i hit the magic 114 on mfa readout!

I popped to the mechanics to get my handbrake cables changed and he reckons it could be the MFA chip behind the cylinder block that is faulty (rationale being that the red light only comes on at a certain temp reading)...will try this next weekend, other than that I am bamboozled   :undecided:

On a positive, did the gsf gear linkeage repair kit this weekend and deffo a firmer feel to the gears!

G