Where does your temp gauge needle sit ?

[Sideways Steve 10]

Hi all,

 

I am curious to see where your needle sits on your 1.8 16v's and 2.0 16v's

 

Whilst driving mine sits bang in the middle (90 deg) but when I slow down in town and in traffic it creeps up to the next line which I guess would be 100 deg. At this point the fan comes on and the temp doesnt go any higher.

 

Is this the same for everyone else ?

[polo_corrado_rims 0]

Hi all,

 

I am curious to see where your needle sits on your 1.8 16v's and 2.0 16v's

 

Whilst driving mine sits bang in the middle (90 deg) but when I slow down in town and in traffic it creeps up to the next line which I guess would be 100 deg. At this point the fan comes on and the temp doesnt go any higher.

 

Is this the same for everyone else ?

 

Yeh mine does this, mine temps to jump around a bit temp wise, it sits just under the 90 a lot of the time, then in traffic or slower town driving tends to rise and stay just above the half way mark but like yours the fan always kicks in to bring it down a little.

 

If you look on the MFA readout at oil temp that gives a good idea of how hot things are getting under there too, max ive seen mine is about 112 on a real hot day (26c+) in traffic.

[Rorgasm 10]

yeh mines the same:shrug:

[Supercharged 2]

If it's going up in traffic then the rad fan switch is not working or the stat is not 'fast' enough... change both of these with fresh coolant.

 

It's important that the cooling system works as it should to not put too much pressure on old Heater Matrixes

[Sideways Steve 10]

New stat, new coolant, new heater matrix, new water pump, new hoses and it still does it LOL

 

Oil temp never goes above 108 though.

 

I wondered if its maybe the fan switch not going on to second speed ? it does come on and blows quite hard but not sure if thats just on first speed or second.

[RW1 0]

My Scirocco 8v does it. As have 5 previous 8 valvers also do this. My Corrado VR6 does it. As long as the rad fans cut in its OK. If you had the rad thermo switch set equal to the running temp, the fans would be on all the time.

 

As long as the temp rises no further and the rad fans bring down the temp. Plus the oil temp follows abeit more slowly either up or down. The engine cooling is normal.

 

Get worried when it carries on up together with the oil temp following with the rad fans on or not working. Then there is something wrong.

 

But for peace of mind, warm the engine up, stick a probe in on the 1st & 2nd stage cooling wires to the fan at its motor casing connector and see if each comes on (ie. 12 volts) or whether you just have a 1st stage or second stage only working.

 

At the fan connector....

 

1st stage is red/white stripe wire.

 

2nd stage is red/black stripe wire

 

I've used a straightened out paper clip to get thro' to the connector on the engine plug side in the past.

 

.

[Sideways Steve 10]

Cheers for that RW1, I will investigate the wires tonight as im also off to test fit some 10" wide minilites to see if they will clear my brakes LOL

[eurospec 10]

Mine sits bang on 80c all the time when driving, when sat in traffic the hottest it has ever got on the gauge is 100c.

Oil temp is normally 95-98c when driving, just over 100c when in traffic, this is on a 2.0 16v (RE2000)

[Purple Tom 0]

The Corrado is fairly dated compared to modern cars when it comes to displaying the temperature reading on the gauge. The gauge is linked directly to the coolant temperature sensor and as such will give a pretty accurate reading of the engine coolant temperature. It's perfectly normal for the temperature to rise slightly when you slow down and enter traffic - the engine is still running and there is little or no airflow through the radiator. Most fan switches come on (first stage) at about 94-95 degrees, but if you look at their position on the radiator compared to the position of the coolant temperature sensor then you'll see why the gauge often reads higher. The fan switch is located at probably the coolest part of the cooling system when you factor in convection due to hot water.

 

More modern cars take their coolant temperature gauge readings from the ECU, which specifies 'normal operating parameters' for the engine coolant. The needle will sit bang on in the middle (often 90 degrees), providing the coolant temperature is within those specified normal operating parameters. So even on a modern car the temperature will fluctuate when stuck in traffic, it's just that the gauge won't show it. That's why its common for VAG 1.8 20V engines with knackered thermostats to read 65deg on the gauge until they sit in traffic for a while and suddenly the gauge jumps up to 90deg - the coolant just gets warm enough to enter NOP and the gauge indicates normal. As soon as the car starts to move again the gauge will drop - 99 times out of 100 changing the thermostat will cure that fault.

 

Don't forget as well good old Boyles law - gas and liquid under pressure. The coolant system is pressurised for a reason - the fact that water (or any liquid) has a higher boiling point when it's under pressure. So providing your cooling system is in good condition with no leaks, and everything is working as it should (stat, pump, rad and sensors), then there shouldn't be a problem.

 

I hope what I've put has made sense - I learned a lot about cooling systems when owning Mini's - those little buggers love to overheat! I built a silly-race-spec (as in lumpy cam, big head, almost totally undrivable and completely inefficient at low revs) 1293cc A-series engine and had to keep it cool in traffic as I needed to drive it to the Nurburgring!

 

HTH!

[Sideways Steve 10]

Cheers tom, makes perfect sense mate, I have just been away from old VW's too long and am used to rock steady needle readings of Jap stuff LOL

 

From what I have read and from having a good look at mine again it all seems perfectly normal so I am happy :) and no more coolant loss either so looks like the repaired flange and new water pump have sorted all of my cooling system issues at last ! :)

[2_Door_fun 0]

Wow I wish my G60 sat at 90 bang in the middle !!! Fitted and Awesome supplied Neuspeed 180 / 82 degree stat at the weekend full system flush and all new antifreeze and checked all the hoses.

 

I have a real Spal fan fitted and its on a manual switch.. As ever the old G60 fan circuit still does not work.

 

There is no way I have ever managed to get a 60 to run sub 100 well only in Winter when you really need a stat to have a heater haha.

 

With the temp outside now around 14 degrees the 60 sits at 100 and the oil is chasing it even with a mocal 8 row cooler.

 

I would like to wire the original fan circuit to the battery maybe with relays... The fan circuit is as poor as the headlamp circuit.

 

Every 60 owner I meet always always asks does yours run hot... I bought a set of adjustable Koni's a week back from a fella Nr Preston and it was indeed the first thing he asked.. We both started laughing.

 

Always interesting to hear theories on the old engine temps.

 

I think its also interesting that Germans being German fitted a gauge with actual readings... Maybe if the gauge read like Fords with Blue for cold and Red for trouble and in the middle was the word NORM it would reduce engine worries lol..

 

I was thinking of getting a sensor kit that sits sits in the top hose.. 82 degrees to match the stat.. Wire it up direct. Would that help the engine some? Or is that really the wrong position for a new sensor?

 

Interesting post chaps..

 

Rob

[guildmage 11]

I knew I saw this thread before... just took me 8 pages to find it.

 

Anyway, it looks like my temps:

[ATTACH=CONFIG]49996[/ATTACH]

... are exactly as they should be. It's rather cold outside nowadays, and was thinking my temps are low... but seems 90 degres it's spot on.

[owen g60 10]

Yep between 90 and 100 even a G60 should be like that... Mine now does after changing the heater matrix and fan

[guildmage 11]

Me again :)

Am I worrying too much?

I know its cold outside so temps will be lower than usual but I did around 15 miles of driving today, first 5 miles done in city at slow speeds, temps were mostly around 70-80mark. Then did around 10 miles on motorway and temps were again very similar. Now then as soon as I stopped on lights temps are going up slowly all the way to 90C but as soon as i start driving again they drop down quite drastically.

 

Is this normal, I though temps should be around 90ish mark all the time, regardless if you stuck in traffic, doing motorway or city driving. Been monitoring temps for quite some time now and they are usually way below 90 when I'm driving.

Also my car being 16v 2.0 - I'm doing around 25mpg on motorway, but in city it's more like 18mpg... I blame cold temps and fact I have 2-3 miles to work so engine will not really get warm up properly.

[fla 9]

Mine is similar, although my stat is stuck despite being replaced last year. my water doesn't go beyond about 80 nowadays and drops to slightly less than 70 on motorways .

[Supercharged 2]

Change your thermostat!

 

Me again :)

Am I worrying too much?

I know its cold outside so temps will be lower than usual but I did around 15 miles of driving today, first 5 miles done in city at slow speeds, temps were mostly around 70-80mark. Then did around 10 miles on motorway and temps were again very similar. Now then as soon as I stopped on lights temps are going up slowly all the way to 90C but as soon as i start driving again they drop down quite drastically.

 

Is this normal, I though temps should be around 90ish mark all the time, regardless if you stuck in traffic, doing motorway or city driving. Been monitoring temps for quite some time now and they are usually way below 90 when I'm driving.

Also my car being 16v 2.0 - I'm doing around 25mpg on motorway, but in city it's more like 18mpg... I blame cold temps and fact I have 2-3 miles to work so engine will not really get warm up properly.

[guildmage 11]

I shall do that then. This will have to wait till January as I am leaving country for xmas.

 

Well there we go, another planned job incoming soon. Also, while replacing thermostat is there anything else I should be replacing while I am it it?

 

ps. I believe, meanwhile, I am OK to drive as it is? I don't do a lot miles on daily basis anyway, just to work and back.

[Tristan H 10]

Mine is also 70-75 when steady motorway driving , anywhere from 40-80 mph , makes no difference! And driving easily , best mpg I'm averaging is 30-32mpg . Oil temps hover around 96 btw . Looks like I need a stat too? And do you guys think it'll help the fuel economy?

[guildmage 11]

Well I just had my thermostat/seal changed as per previous advise + new coolant off-course and it fixed "the-low-temp-issue" for me. Once temps climbed to 90ish it stayed like that when driving and slightly climbing when stuck in traffic.

 

Happy again, cannot yet comment on economy as not enough driving since change... but will report back.

[Supercharged 2]

Nice one! - it's good to have some feedback when problems are sorted...

 

It should pretty much sit at 90 once warm, if it's getting near the 100 mark in traffic then you may also want to change the thermoswitch on the radiator too.

[Wendy 0]

Change your thermostat!

 

Why ? Sorry not understanding.

 

If the car is sitting at 75 - 80 for normal running.

Sat in traffic rises slowly to 90 -100

Moving off again slowly drops back down to 75-80

 

Why is that wrong, surely all cars (of ours ages anyway) will get warmer when sat in traffic and then drop again ?

 

Do I get the impression, it is being suggested more fuel will be used if this is not running correctly too.

What has fuel usage got to do with car running temperature - that really not make any logical sense to me.

 

Really guys - please explain - in very basic terms too.

Thank You

[Critical_Mass 10]

my VR used to ALWAYS sit at 90 when moving, it would rise in traffic. Now since changing the rad and flushing the coolant, it will sit at 80 rise in traffic but then drop again. Im certain it should sit at 90 when moving and rise in traffic to the point where the fans will come on, allowing it to drop to 90~ again.

 

If the stat is stuck open the water will take longer to heat up as the water is passing through the rad. It will use more fuel until up to temp and no longer in cold start mode.

[tentonhammer 10]

75 at 30mph, and 90 stuck in traffic. This is apparently normal, even though I have an unrelated flashing temp light on my dash... !! Suspected faulty / gunked up sensor in header tank.

 

Note: Temp levels have always been like this even before the flashing temp light.

 

C 16V 2.0

[guildmage 11]

hmm I'm also with 2.0 16v and when I bought the car it was 90ish preety much all the time, in traffic was going up, but the fan was kick-in to drop temp down.

Then something happened (aka faulty thermostat) and I had constant 70-75ish temp regardless of my driving - but when stuck in traffic, temp was going up to 90ish.

 

So I had thermostat replaced (as explained in this thread) and now it's all back to normal. It takes time to get to 90 but once at 90 it stays like that regardless of my driving, or me being stuck in traffic.

 

Time will tell what is going to happen once we will hit proper hot days during summer.

 

Also, fixing my temps had little impact on economy... yes I can see it showing me a bit more out of the gallon but its not amazing improvement. I still to do some long distance driving to properly check this out, cause my 2-3 miles to work are hardly any test at all :(

[davidwort 0]

Why ? Sorry not understanding.

 

If the car is sitting at 75 - 80 for normal running.

Sat in traffic rises slowly to 90 -100

Moving off again slowly drops back down to 75-80

 

Why is that wrong, surely all cars (of ours ages anyway) will get warmer when sat in traffic and then drop again ?

 

Do I get the impression, it is being suggested more fuel will be used if this is not running correctly too.

What has fuel usage got to do with car running temperature - that really not make any logical sense to me.

 

Really guys - please explain - in very basic terms too.

Thank You

I'll have a go from my understanding.

The thermostat and radiator fans/temp switches are designed to keep the water flowing into the engine for cooling at the optimum temperature for engine efficiency as it was designed.

So ideally the temperature on your gauge should not rise when you are in traffic, or drop when you move off at a fair speed/airflow, it hasn't really on any of the cars I've owned when everything is as it should be on the engine. Having said that, the mechanical nature of a thermostat means it doesn't respond (open/shut) immediately, different stats can vary slightly, as can the on/off temperature of the fan sensors.

Comparing the oil and water temps can often help tell you what's going on too.

Fuel doesn't vapourise well at low temperatures, so on the warm-up the fuelling is designed to provide a richer mixture to compensate for this. So more fuel is delivered to obtain the same power output from the engine and make it run smoothly. If your thermosat sticks open, the water is cooled too much, so the engine block, cylinders and head gets cooled too much and the ECU/fuel system will deliver a richer mixture to compensate, like it was on the warm up phase.

In theory, cold weather means more dense air so more power and better efficiency, so long as the engine temp is controlled correctly. In reality, during the winter the warm up takes longer, you have lights, HRW, fan on for demist etc. so most people use way more fuel.

Newer engines with more efficient designs, smaller coolant capacities and wide-band lambda sensors are much quicker to warm up and better at metering fuel so the ambient temp makes less of a difference.