Temperature Guage Readings

[hiltow]

I was just wondering if someone could confirm exactly what position the temperature gauge needle should point to on a 1.6 EW/1.8 mk2 DX when the engine has warmed up and the car is travelling at a constant speed? (i.e. on a standard car).

Seems a daft question I know, but when my car's in use the left hand edge of the needle flank is about 1mm past the edge of the engine warning lamp LED (i.e. to the right of the lamp).

In this position the point of the needle appears quite far over, so I'm just worried there might be a problem and wanted to know what others'

In the past I seem to recall the needle pointing straight up (half way) when driving at a constant speed of 30mph+.

What is it with '80s era water-cooled VWs? I had a Mk2 Polo years ago and it behaves much like my Scirocco - it never takes much for cooling fan to kick in when compered to other cars I've owned.

[ghost123uk]

Sounds OK to me, mine settles in about the same position.

[scirocogtx]

My Scala's the same, slightly right of centre.
Seemed to go from being in the middle between cold to the centre to this after I changed the vw thermostat (original?) to a non vw one.

My GTX runs between cold and centre on the original or oe thermostat.

[hiltow]

I have the OE thermostat scirocogtx, but my car always used to run with the needle pointing straight up half way when running constantly. The car's a 1.6 carb'd GT with the EW engine.

I hadn't used the car regularly for two years until August this year. The engine coolant was flushed/changed prior to this. I also fitted a new VW radiator as well, so half the coolant was renewed again.

Maybe I need to have the engine flushed again, but it's bugging me that the car suddenly seems to be running hotter.

I had the distributor refurbished due to a fault and the carburettor also refurbished. The emissions on the carb and the distributor timing have been set properly, so hopefully this shouldn't be affecting the running temperature. I've also changed the temperature gauge sensor for a new one from VW.

The car's put away now for the winter, but a couple of weeks ago when it was fine I took it out down the motorway at a steady 60mph, but the gauge just seemed to want to go up towards three-quarters, which concerned me a bit. I put the heater on full-blast, but it didn't make much of a difference. I left the motorway and pulled over to open the bonnet, but nothing seemed amiss. I just couldn't understand it as it seemed to be running hotter when the November outside ambient temperature was 7c than it ran earlier in the year when it was 20c outside.

It just bugs me that it's started doing this as I'm worried I'm coing to fry the engine.

Incidentally, I know this sounds bonkers, but when I had the fan on high speed, occasionally there was a farily lound intremittant hissing noise coming from behind the instrument panel that sounded just like the radio was on FM but not tuned into a station. Unless some debris is trapped in the ventilation supply pipe behind the dash, christhemann's previous post about a warning buzzer behind the dash has since got me thinking could it be that?

[ghost123uk]

It just bugs me that it's started doing this as I'm worried I'm going to fry the engine.

I would'nt worry, bleed it again to be sure and keep an eye on it next time you use it, but, imho, it ain't a problem.

Incidentally, I know this sounds bonkers, but when I had the fan on high speed, occasionally there was a farily lound intremittant hissing noise coming from behind the instrument panel that sounded just like the radio was on FM but not tuned into a station. Unless some debris is trapped in the ventilation supply pipe behind the dash, christhemann's previous post about a warning buzzer behind the dash has since got me thinking could it be that?

Likely a leaf stuck in the heater duct or blower fan.
If it was the oil buzzer you would know it for sure !

[eamon1.3]

The car's put away now for the winter, but a couple of weeks ago when it was fine I took it out down the motorway at a steady 60mph, but the gauge just seemed to want to go up towards three-quarters, which concerned me a bit. I put the heater on full-blast, but it didn't make much of a difference. I left the motorway and pulled over to open the bonnet, but nothing seemed amiss. I just couldn't understand it as it seemed to be running hotter when the November outside ambient temperature was 7c than it ran earlier in the year when it was 20c outside.

At speed mine were always under the half way mark, especially when it was cold out side.

[fonzooorooo]

On my EX GTII i sits just over half way up. Fan cuts in when it gets up to the dot 1/2 way up the right half of the gauge. Mine used to run hotter before I changed the water pump. (it was getting a bit noisy.) While the pump and pipes were off, I pressure washed all teh waterways out... Not sure I'd recommend anything that severe, but it worked for me! Washed loads of rust/general grot out.

As for the noise in the dash, yes, it'll more likely than not be leaves. There's no guard to prevent them getting sucked in. You can normally free them with the air vents set to dash only, centre vent shut, one of the side vents shut, and opening/closing repeatedly the other side vent. (fan on 3 all the time)... If they don't come out of one side doing that, they usually come out of the other.

A lot of people on here have suffered with dodgy thermostats. (I've had a couple that've only lasted a year) Also, ignition timing being out can cause hot running.

[scirocogtx]

I was going to say to check that the water pump is working properly, that there is a strong jet going into the expansion tank, even at idle, and not just a dribble. If its a dribble then either you've a small leak/weep somewhere in the system or the pump is not working efficiently. I'd also check that the sensor is clean and not covered in slime.

The temp sender should have a resistance across its terminals of around 2000/2500 Ohms when cold (20 C)and about 200 Ohms when hot (90 C) if is working properly. Maybe worth checking.