Coolant Temperature Readout

[mopardave]

Today, I noticed that the coolant temperature gauges were out of sync! The analogue one didn't move off zero for several minutes and the digital one appeared to lag behind the analogue gauge.....so when the analogue gauge eventually got up to 90 degrees, the digital gauge was only reading 60 degrees. I noticed the analogue gauge sticking on zero a while a go when it was really cold....but I'd left the heater fan on setting 1 from the night before so just assumed it was slow because I was (unintentionally) demanding warm air into the cab when I should've been letting the engine warm up first. I hope that makes sense.....seems a bit long winded but I can't explain it any other way? Has anyone else noticed a discrepancy between analogue and digital temp gauges? I'm sure they were the same in the past???

 

[Dieseldonkey]

Is your digital gauge definitely for coolant temp as opposed to oil temp? On my dash I only have analogue for coolant and digital for oil. In which case the oil always lags behind the coolant up to about 90 degrees. Then the oil normally keeps climbing to between 100 and 110 degrees.

 

[mopardave]

Is your digital gauge definitely for coolant temp as opposed to oil temp? On my dash I only have analogue for coolant and digital for oil. In which case the oil always lags behind the coolant up to about 90 degrees. Then the oil normally keeps climbing to between 100 and 110 degrees.

oooh.....never thought of that @Dieseldonkey .....you're probably right! It would make perfect sense.....but, the digital one never goes beyond 90 degrees.....and nor does the analogue one. Is this a coincidence? In any event, the analogue one didn't move until I'd done about 3 miles....I'm pretty sure it usually moves quicker than that?

 

[Dieseldonkey]

In terms of water temp, every VAG diesel I've ever owned sits at 90 once its warmed up. I've noticed variation in warm up times with the T6. However, I've got an auxiliary coolant heater that kicks below a certain ambient temperature, so that's explainable. I'm sure I read a thread on here, where folk were quoting oil temps in excess of 100 degrees. So I'm guessing that's the norm.

Just a thought, might be worth double checking your oil level to make sure you don't have too much in the sump, if your oils running cool.

 

[Lord Mfwic]

My Oil temp frequently runs at 105, this gives a good indication to lighten my foot on the throttle.

 

[mmi]

In terms of water temp, every VAG diesel I've ever owned sits at 90 once its warmed up.

Yes, that's the way the analogue gauges are designed by VW. The explanation below.

 

[Dieseldonkey]

Now that is interesting @mmi .

So not only have VW been didling my emissions for all these years, they've had my temperature gauge committing fraud too.

Where's my tin foil hat. They're definitely out to get us.

 

[Loz]

Well done @mmi I was searching for that..

 

[Dieseldonkey]

Re oil temp. Why do they feel a need to plateau an analogue oil temp gauge yet the digital read out on the MFA seems not to behave like this?

 

[mopardave]

In terms of water temp, every VAG diesel I've ever owned sits at 90 once its warmed up. I've noticed variation in warm up times with the T6. However, I've got an auxiliary coolant heater that kicks below a certain ambient temperature, so that's explainable. I'm sure I read a thread on here, where folk were quoting oil temps in excess of 100 degrees. So I'm guessing that's the norm.

Just a thought, might be worth double checking your oil level to make sure you don't have too much in the sump, if your oils running cool.

I'll watch the oil temp readout....but I'm sure it max's out at 90.....hmmmmm? I'll check the oil level anyway out of curiosity.....but there shouldn't be too much in 'cos I did it.

 

[Lord Mfwic]

I'll watch the oil temp readout....but I'm sure it max's out at 90.....hmmmmm?

Mine gives a varied read out from 60-120. I have it as my main MFD display.

 

[Robert]

Yes, that's the way the analogue gauges are designed by VW. The explanation below.

View attachment 20495

I know it is automotive industry standard to keep vehicle users convinced that their vehicle temperature is regulated in such a perfect manner.

On all of my Passats I have had modified IC eeprom to get linear coolant temperature characteristic.
I simply prefer to see exactly what the real temperature is and I don't need to be fooled.
I like when temperature hoovers around 90°C and follows engine load pattern.

 

[Loz]

I wish it would be so simple on a T6 IC.

Trouble sleeping?