GolfGTIforum.co.uk

Model specific boards => Golf mk3 => Topic started by: thebassman on 28 November 2010, 16:24

Title: Engine temp
Post by: thebassman on 28 November 2010, 16:24
Bit of a noobie question.
Is the temp gauge on the left hand side, under the rev counter, water temperature?
Is the temp shown in the dash computer display oil temperature?

Do they normally read the same?

Cheers

Thebassman
Title: Re: Engine temp
Post by: dom on 28 November 2010, 16:39
MFA = Oil Temp

Temp Gauge = Water Temp

When warm my oil temp can be anywhere between 98-104 depending on the type of driving and water temp is usally smack bang in the middle (90 I think).
Title: Re: Engine temp
Post by: thebassman on 28 November 2010, 16:49
That weird, I had been driving for about half an hour, quite hard.
The water temp was about 70'ish and the oil temp was 74.
Title: Re: Engine temp
Post by: whitey82 on 28 November 2010, 17:15
I've got same problem with gauge sat on 70 all the time and occasionally moving so I've ordered a new temp sender,hope that cures it
Title: Re: Engine temp
Post by: dom on 28 November 2010, 17:22
I've got same problem with gauge sat on 70 all the time and occasionally moving so I've ordered a new temp sender,hope that cures it

Have you tried changing the thermostat?
Title: Re: Engine temp
Post by: whitey82 on 28 November 2010, 17:26
No I haven't,only had the car 2 days but read that the water temp sender is a commen fault so for sake of 8 quid thought id give it a go. Where abouts is the thermostat and is it easy to replace? What's the cost,cheers
Title: Re: Engine temp
Post by: dom on 28 November 2010, 17:33
No I haven't,only had the car 2 days but read that the water temp sender is a commen fault so for sake of 8 quid thought id give it a go. Where abouts is the thermostat and is it easy to replace? What's the cost,cheers

The thermostat is only a few pounds, where it is depends on which engine you have? and how easy it is depends on whether or not you have PAS?
Title: Re: Engine temp
Post by: whitey82 on 28 November 2010, 17:58
It's a 2.0 8valve with pas
Title: Re: Engine temp
Post by: dom on 28 November 2010, 18:14
It's a 2.0 8valve with pas

The thermostat is located by the waterpump, if you look from above you'll be able to see it to the left of your pas belt/alternator belt.

I read somewhere that you can tell if its your thermostat that is faulty by feeling the pipes above and below the thermostat housing when the engine is warm, if both pipes are warm there is no problem but if only one pipe is warm the thermostat is not opening and therefore shot. The theory behind that is good but whether or not it's true I don't know!  :smiley:
Title: Re: Engine temp
Post by: thai-wronghorse on 29 November 2010, 07:54
as mentioned above, change the thermostat. Id personally change the pas, auxillary belt and water pump whilst they're stripped out as well for good measure and to save having to do the job twice.
Title: Re: Engine temp
Post by: thai-wronghorse on 29 November 2010, 07:56
For the record the water temp gauge should sit in the centre (90 degrees) once the engine has warmed up.
Title: Re: Engine temp
Post by: rubjonny on 29 November 2010, 10:39
to check the stat run ebgine from cold and feel bottom rad hose. it should stay stone cold till gauge gets to the middle, then it should get hot. if it gets warm almost straight away stat is missing or stuck open.  need to drop the pas pump and brackets off the engine, not hard only a couple bolts and whole thing drops off the bottom. dont even have to undo the pas pipes. just undo the brackets about half way along front of car holding pipes up and drop it down and shove to 1 side
Title: Re: Engine temp
Post by: Khare on 29 November 2010, 15:03
To check thermostat start the car from stone cold and feel the top and bottom radiator pipes. If they warm up at the same time the thermostat is stuck open, if the top pipe gets really hot and the bottom one is still cold, then when the temp gets to about 84ish degrees and the bottom starts to warm up, then it's fine.

Another common thermostat sign is when driving the temp will be 70ish, and when stationary for a while it will rise to 90 (where it should be).

Couple of quid from GSF or the likes and shouldn't take more than 20 or so minutes to change. Remember the cooling system will drain completly so you'll need new antifreeze.
Title: Re: Engine temp
Post by: whitey82 on 29 November 2010, 17:24
just did the test with car sat on the drive,started her up and top rad hose started to get very hot within about 5 mins or so and the bottom hose just stayed cold, the gauge in the car just sits on 70 all the time. Im i right in thinking the thermostat is ok then and ive ordered a new temp sender so hoping that might cure it?
Title: Re: Engine temp
Post by: Khare on 29 November 2010, 21:15
Stat seems fine then, probably a bad temp sender then. Can't remember on the 8v, but the 16v at least has one for the ECU and one for the dash.

Title: Re: Engine temp
Post by: spunkymonkey on 29 November 2010, 22:24
If your top pipe is hot but the bottom pipe is cold you have a stat issue. Just drop the power steering pump leaving it hanging on the pipes and remove the plastic elbow. Theres your thermostat.
Title: Re: Engine temp
Post by: whitey82 on 29 November 2010, 22:32
I'm confused now,I thought if the top pipe is hot and the bottom stays cold for a while then its ok,thought the fault was when they heat up at the same time? The bottom does start to warm up after about 10 to 15 mins
Title: Re: Engine temp
Post by: dom on 29 November 2010, 22:36
I'm confused now,I thought if the top pipe is hot and the bottom stays cold for a while then its ok,thought the fault was when they heat up at the same time? The bottom does start to warm up after about 10 to 15 mins

I would have thought unless both pipes are hot you have a thermostat issue, if one is cold it is because the thermostat is not opening and therefore knackered!
Title: Re: Engine temp
Post by: Khare on 29 November 2010, 23:00
If your top pipe is hot but the bottom pipe is cold you have a stat issue. Just drop the power steering pump leaving it hanging on the pipes and remove the plastic elbow. Theres your thermostat.

The bottom pipe must heat up at some point otherwise water is just circulating around the engine rather than radiator, and engine temp would be sky high rather than 70.

It won't be stuck closed otherwise you'd have blow headgasket a while back.

You have either a dodgy stat, or a dodgy temp sender.