cool flash

Hello,

since 2 days my oil and water temp gauges are acting up: oil temp gauge needle moves up a little bit but falls short of usual reading by about 2 increments. The water temp gauge moves somewhat irratically (rises and falls) and takes much longer to move to its usual dead center position.

The electronic oil measurement function (electronic dipstick) still works as usual.

The heater stays too cold. However, the windshield defrost setting produces adequate warmth.

Anyone any ideas of what could be the cause.

Regards,

CF

Macster

The behavior could be electrical, something amiss in the gage cluster.

But the heater staying cold suggests there could be a mechanical explanation, which could be a failing T-Stat.

Because running the engine with a failing T-stat is to be avoided you need to have this looked into.

Probably the cold engine will be started and let idle while on the lift and periodically the tech will check the hoses from/to the water pump checking to see if they get warm as the coolant warms up and as the T-stat should start to open to allow coolant to flow to the radiators. Or the T-stat opens too soon, or is stuck partially open in which case warm coolant circulates too soon. Or the tech may have another way to check for a proper functioning T-stat.

If the T-stat (and water pump) is eliminated then this suggests the problem is electrical in nature and the tech can then investigate the cause from that angle.

Bruce In Philly

Hooking up to a Durametric will allow you to read oil and water temps. Since I own one, I would hook it up to see first, if there are any deep codes thrown, and then moniter the oil and water temps rise from cold. I have done this in the past a few times and I know the rise in oil and water temps is fairly linear up to operating temps (fairly regardless of load).

I would assume, given that I am a brain surgeon/child behavior expert/internet guy..... If the rise in temps was linear and as expected, I would assume something with the gauge cluster. If the temps were not linear, then I would expect something with the temp regulatory system such as the the T-stat.

And then I wouldn't know what to do.

Peace
Bruce in Philly

Philster

T-Stat or head gasket come to mind given the symptoms, and I'd not drive the vehicle until it is checked out.

If the heater function wasn't mentioned, it would be much more confusing.

.

cool flash

Thanks for all replies.

I just drove the car for two hours on the autobahn (since I had to get home). The gauges are back to their normal readings, however, the dash vents still blow coldish air.

I have an appointment with my indy tomorrow to activate the SportChrono so I will get the car scanned for errors.

I will post tomorrow when I have more intel.

Regards,

CF

cool flash

Went to my Indy today and his PIWIS showed us the following sporadic error: "thermostat stuck on open". Since car has been fine since no further action needed.

On another note, as mentioned earlier I also got the SportChrono+ activated. PDK + SportChrono is simply awesome. Well worth the money (€1000+).

Regards,

CF

Bruce In Philly

This is very interesting, thank you for sharing the results.

I always suspected the computer controls thermal management. I know this is not proof of it, but I'll bet the computer is controlling that thermostat. Of course, it could be inferring this problem from other data, but my gathered evidence suggests something more sinister... the computer is in charge.

See my thread here on my Durametric readings of Oil Temp, Water Temp, and engine/car speed over time.

https://rennlist.com/forums/997-foru...tric-data.html

Peace
Bruce in Philly

cool flash

I suspect that the thermostat was actually (mechanically) stuck. But I am no mechanic...

CF