temperature guage problem and driving?

[mrggg]

I know this has been covered before but my guage is fluctuating between 70 and 90 degrees. I just wanted to know is it ok to drive the car, especially long distances? I will be servicing the car on thursday but need to get around, should I keep the revs low and change at 2k?

Thanks.

[Bo!]

loads of threads on here about this .
When does is it fluctuate .?
Mine is in VW now for this exact reason temp drops under engine breaking from 90 down to 70 I suspect it could be a stat issue , driving mine for a month before it went in to VW just not hard .

[Dan_FR]

Does the service include changing the thermostat? If not, then add it

You can drive it around, although I personally wouldn't hammer it about as you'll never be getting it up to temperature. 70-90 on the gauge is more like 60-75 degrees C, not the 90-92 it would normally run at

[lukemk5gti]

You can drive it around, although I personally wouldn't hammer it about as you'll never be getting it up to temperature.

It will get up to the temperature, it just won't reflect it on the display. Typically it takes 20mins of driving to get to 90deg (completely weather dependant) so if you're doing an hour long commute you're safe to give it a bit of throttle near the end even if the display shows 70.

[Dan_FR]

The display reflects the coolant temperature, it is a direct measurement of the temperature. The oil temperature will eventually warm up to an acceptable-ish temperature, but still not to the temperature it would be if the thermostat was working correctly. You also get reduced performance as the timing/fuelling maps differ when the car is not up to temp

20 minutes? Mine takes about 5 minutes, 10 at the most if its cold outside, and usually less than 3 miles to show 90 on the gauge

As I said, me personally, I would get it fixed and not drive it hard.... but then again my car doesn't ever see boost until the gauge is firmly on the 90

[lukemk5gti]

The display reflects the coolant temperature, it is a direct measurement of the temperature. The oil temperature will eventually warm up to an acceptable-ish temperature, but still not to the temperature it would be if the thermostat was working correctly. You also get reduced performance as the timing/fuelling maps differ when the car is not up to temp

20 minutes? Mine takes about 5 minutes, 10 at the most if its cold outside, and usually less than 3 miles to show 90 on the gauge

As I said, me personally, I would get it fixed and not drive it hard.... but then again my car doesn't ever see boost until the gauge is firmly on the 90

Maybe I had that wrong, I know the dial on the display reflects coolant temp but I was under the impression that it was reaching the appropriate temperature but due to the faulty thermostat it just didn't reflect it. i.e. physically it's fine but the electrical output didn't reflect this?

During summer I was at 90deg no problem, last Winter the thermostat failed and I replaced so it would reach 90 again but during colder months here on the windy seaside my evening commute to the gym is 23mins and depending on how cold it is I'll be at 90 in either 10mins or 20mins!

[Dan_FR]

Other way round, the gauge can reach 90 but may not mean the engine temperature is genuinely 90.... The dash will read 90 anywhere from a true 75 degrees C to well over 100 degrees C, so even when the dash is showing the 90 the car could be running 15-20 degrees cooler than it should. An indicated 70 is more like 60 degrees C from memory

You're thinking of the coolant temperature sensor, this can malfunction and give a cooler reading on the dash than the actual temperature, which could still be correctly maintained by the thermostat

[Pesky jones]

I had/have an issue with my coolant temp

Would float around 50-70 even after an hour or so of driving.

Replaced main stat, it now gets up to temp, but like lukes after about twenty minutes. Even then it can get to id say 85 on the gauge and float around down to 80ish but once its at 90 it stays there.

I think I need to replace the two inlines (DSG) but im waiting for the summer to do that.