VW Bora water temperature gauge act erratically

leonlafrite

Hello All,

My 00 VW Bora 1.4 petrol water temperature gauge started to act erratically a few days ago…
From Cold it will go up a little after a few miles them will go down to 0 and stay there for about 5 miles and them will go up to the correct 90 Celsius and will go up and down again randomly ... so far it never went over 90 so I do not think it is overheating .
The speed to which it does is immediate and very quick too…
Now my question is what can be the problem… water pump or some sensor?
I am afraid that if I go to a garage they will “do” me for a full waterpump deal when the problem could only be the sensor …
The Timing Belt Kit( water pump) was changed a little less than 2 years ago..

How can I approach this???

Thank you !

Anan1

Start by checking your coolant level, low coolant can cause funny readings if the level falls below the sensor.

peasant

First check that your coolant level is alright, then check that the heating still works properly and then find out if your radiator actually gets hot after a while

With all of those ok you're probably just looking at an electrical gremlin.

Neilw

The coolant temp sensor is know to give trouble, check if it's a black sensor, these are the ones which give trouble and have been updated to a green sensor.

voxpop

+1 on what Neilw said. Temp sender

leonlafrite

Guys thank for the quick responses,

So far I know that :

The heater is working fine

I will check the coolant level & radiator later (I think it is ok)

Where is the coolant temp sensor located :-) ?

Cheers.

Neilw

leonlafrite wrote: »

Where is the coolant temp sensor located :-) ?

In the engine bay only joking, not sure on the 1.4 engine but on mine it's on the right hand side of the engine when looking from the front. IIRC the sensor sits into a housing on one of the coolant hoses, so long since I changed it I can't remember too well.

crosstownk

As posted by Neilw, coolant temperature senders are known to give problems on that model. It's item 10 in the illustration below. It's black in colour with a green band around it (older sensors may have a yellow band). You will loose coolant if you attempt to replace it so be sure to have spare coolant ready to top up the system. Only attempt to replace it when the engine is stone cold. It comes out handy enough, all you need to do is to pull back the retaining clip. If you do buy a new sensor then be sure to also buy a new seal for it. Any VW dealer will supply you with the correct part once you can quote the engine and/or chassis number. I'd imagine that a 2000 1.4 engine is an AHW engine.

As far as I can make out the parts you may require are 059 919 501 A (temp sender) and N 903 168 02 (seal), you'll also need a bottle of G12 coolant. You'd be best off to run these numbers by a VW dealer first as the catalog I'm looking at (www.vagcat.com) may not be 100% up to date.

leonlafrite

Hi crosstownk, Neill and all

Thank you for yor suggestions, I will get a new sensor today (plus seal)
So basically the seal is number 15 in the drawing and I need to replace it also.
I am not that goof in mechanic but this is a small job right ? Cannot really go wrong ?

Thanks I will keep you posted.

Neilw

leonlafrite wrote: »

Hi crosstownk, Neill and all

Thank you for yor suggestions, I will get a new sensor today (plus seal)
So basically the seal is number 15 in the drawing and I need to replace it also.
I am not that goof in mechanic but this is a small job right ? Cannot really go wrong ?

Thanks I will keep you posted.

Get the retaining clip no. 14 too, just in case you break the existing one removing it. They are only a few cent.
As for changing it, only attempt to do it with the car stone cold, dont want to get burned by scalding hot coolant. It's an easy enough job, I lot hardly any coolant when changing the sensor in my car.

Pull the clip fron the side, pull out sensor, new sensor with o-ring in and replace the retaining clip, simple as that

voxpop

just to pip in here. I did this on my golf and everyone said it was easy peasy. Took me about 4 hours - lol -I put the new sensor in and when the car heated up, it would come loose and all the coolant would come gushing out. What a fun day. I used the old clip and o-ring (lost the new o-ring, so maybe buy 2)

About 3 months later the sensor came out again while in cork!! Luckily I have a 2L bottle of pre-mixed coolant in the boot for just such and occasion.

Anyway - made it back from cork without incident and got a new clip +o-ring(s) from the dealers - re-seated the sensor and bobs your uncle. No problems since.


Moral of the story - get plenty of coolant, new clips,o-rings and budget for a few hours in case it all dont go to plan - btw mine only leaked when the engine was up to temp - so most of the time was getting the engine up to temp, see the coolant gushing out, wait for everything to cool, re-seat the sensor, re-fill the coolant and try again. Dont know why they didnt just go with a screw in sensor instead of all the messing with plastic clips:rolleyes:

leonlafrite

as VW wants to charge me 45 + VAT (+parts) for this I will chance it myself...but I will get a few spare clip and o-ring just in case ;-)

thank you all.

voxpop

Yeah dont get me wrong - it *should* be a simple straight forward job. Just dont do it sat morning and then drive to galway or something

simonbyrneno.4

Hi guys,

Was just reading your help hints on this and i'm having a problem with a car i recently bought. I'm absolutely useless with cars first and foremost may i say.

It's a 97BMW 316 and the temperature gauge doesn't go past cold at all no matter how long the car is driving.(i know it normally takes abot 10 mins for the car to warm up and then hits a steady level half way on the gauge). As a result the heating doesn't work in the car, it just constantly blowsout cold air. The car seems to be driving properly so far, haven't had any problems with it at all, have it two weeks and it's been up and down to wicklow a couple of times(at least an hour long drive).

Any help at all would be appreciated, don't want to go to a garage and then get stung for loads of things that aren't really wrong with it

voxpop

If the heater is not blowing out hot air then you should check that you actually have coolant in the car. Hot air from the heater comes from the coolant sloshing around your engine. No hot air could mean no coolant - if so, your car could be fecked

Btw - make sure you are not putting water in the windscreen wiper reservoir, rather than in the coolant system. It seems silly, but Ive know ppl to do that

simonbyrneno.4

voxpop wrote: »

If the heater is not blowing out hot air then you should check that you actually have coolant in the car. Hot air from the heater comes from the coolant sloshing around your engine. No hot air could mean no coolant - if so, your car could be fecked

Btw - make sure you are not putting water in the windscreen wiper reservoir, rather than in the coolant system. It seems silly, but Ive know ppl to do that

Hmmm i don't like the first suggestion at all. I'd be extremely unhappy if thats what it was. how do i check if there is coolant in the car? Silly question i know but i really dont know much about cars. and if there isn't coolant in the car then what should i do??

Thanks for the quick reply

voxpop

Tbh - im not sure on a BWM. There is usually an expansion tank somewhere - shaped like an oval maybe.


Driving with no coolant, can cook your engine and results in broken engine and a cylinder head job - which is big money.

simonbyrneno.4

voxpop wrote: »

Tbh - im not sure on a BWM. There is usually an expansion tank somewhere - shaped like an oval.


Driving with no coolant, can cook your engine and results in broken engine and a cylinder head job - which is big money.

Is that only if it goes?

voxpop

If you run your car with no coolant you will seriously damage the engine.

Maybe someone else on here with some BMW knowledge can tell you how to check the coolant level - otherwise I would get a mechanic to do it.



Btw - if you do go to check coolant - dont open the coolant reservoir when the car is warm - the coolant (if there is any), will be hot and can spray out.

leonlafrite

ok, I am trying to find the actual sensor :-( anyone can post a pic or somthing as I cannot find it ...

the car is a 2000 VW bora 1.4 16V ..

cheers

gibbon75

Simon,

I'd say your problem is a faulty thermostat.
How is the fuel consumption? Did she get heavier on the petrol when this problem started?

DaMonk

My thermostat went on my bora and I cooked the head gasket....on a diesel!

Darragh29

leonlafrite wrote: »

I am afraid that if I go to a garage they will “do” me for a full waterpump deal when the problem could only be the sensor …
The Timing Belt Kit( water pump) was changed a little less than 2 years ago..

How can I approach this???

Thank you !

Anan1 wrote: »

Start by checking your coolant level, low coolant can cause funny readings if the level falls below the sensor.

+1 with the advice on coolant level. It sounds like it could be a thermostat problem but you'll have to get this diagnosed fully. I wouldn't be overly concerned with the garage trying to "do" you. If this is your gut feeling with regard to your garage, I'd be looking elsewhere...

leonlafrite

well found it chnaged it , seeme ok will keep it runing for a while but it is now hot as befroe and the indicator stay on the 90 mark, so can I be confident enought or shoudl I book it in ?

Neilw

The temp gauge should sat at the 90 degree mark during normal driving, it usually takes about 3 or so mins driving for the gauge to reach this point from cold.

Once it's not going way above 90 degress you should be ok.
Is the coolant level ok?
Are the cooling fans kicking in?

Keep a close eye on it for the next few days.

limericklad87

i have a similiar problem with my almera.... now and agin all the gauges will read zero or the speedometer will stick along with the rev counter

it doesn't affect the cars performance in any way ie electrics or power steering and an auto electrician was saying that it would be 400 euro to replace all the dials........... no thanks