Weird temp gauge readings this AM

theprf
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Re: Weird temp gauge readings this AM

Post by theprf » Thu Nov 10, 2022 1:43 pm

The temp sensor is an NTC resistor so it is very unlikely to misread, certainly not like the oil pressure sender which has a moving arm that wipes a resistance.
I would unplug and replug the sensor just in case some corrosion got on the terminals. The AMP Mini-Timer contacts are self cleaning when they get plugged in.
If you have an OBD2 reader keep it handy, that will show the gauge is tracking the engine - or not. Don't need durametric for this as engine temp is standard OBD2 protocol so even a cheapie will work. If you haven't got a cheapie OBD2 reader I hear that Jeff Bezos can deliver one via drone... :lol: .

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32wildbilly
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Re: Weird temp gauge readings this AM

Post by 32wildbilly » Thu Nov 10, 2022 2:50 pm

5chn3ll wrote: Thu Nov 10, 2022 1:43 pm Heh.

I performed a full Italian tune-up on the way home from the office, and no shenanigans were noticed.
So you wound her all the way up to 72mph then?
Never gonna make you cry...

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5chn3ll
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Re: Weird temp gauge readings this AM

Post by 5chn3ll » Thu Nov 10, 2022 2:59 pm

In 2nd…
32wildbilly wrote: Thu Nov 10, 2022 2:50 pm
5chn3ll wrote: Thu Nov 10, 2022 1:43 pm Heh.

I performed a full Italian tune-up on the way home from the office, and no shenanigans were noticed.
So you wound her all the way up to 72mph then?

Understeer: You will hit the wall with the front end.
Oversteer: You will hit the wall with the rear end.
Horsepower: How hard you will hit the wall.
Torque: How far you will move the wall.

Gone hunting with Alec Baldwin and Dick Cheney. Back soon.

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5chn3ll
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Re: Weird temp gauge readings this AM

Post by 5chn3ll » Thu Nov 10, 2022 3:05 pm

I’m not familiar with the guts of the 996-specific temp sensor, but I assumed it was a standard thermistor and that it probably wasn’t the problem. The consistency of the issue is what threw me off - the gauge was tracking like normal, but offset ~15% high.

Thanks for your comments and insight. If it reproduces, I’ll start troubleshooting. For now, I’m going to chalk it up to my 996 being pissed I haven’t been paying it enough attention.
theprf wrote: Thu Nov 10, 2022 1:43 pm The temp sensor is an NTC resistor so it is very unlikely to misread, certainly not like the oil pressure sender which has a moving arm that wipes a resistance.
I would unplug and replug the sensor just in case some corrosion got on the terminals. The AMP Mini-Timer contacts are self cleaning when they get plugged in.
If you have an OBD2 reader keep it handy, that will show the gauge is tracking the engine - or not. Don't need durametric for this as engine temp is standard OBD2 protocol so even a cheapie will work. If you haven't got a cheapie OBD2 reader I hear that Jeff Bezos can deliver one via drone... :lol: .

Understeer: You will hit the wall with the front end.
Oversteer: You will hit the wall with the rear end.
Horsepower: How hard you will hit the wall.
Torque: How far you will move the wall.

Gone hunting with Alec Baldwin and Dick Cheney. Back soon.

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Re: Weird temp gauge readings this AM

Post by JayG » Fri Nov 11, 2022 5:52 am

Post the question on 986forum.com
there are several really good Porsche indy's there
2004 Boxster S 6 speed - DRL relay hack, Polaris AutoTop DIY (sold)
2004 996 Targa Tip
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gnat
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Re: Weird temp gauge readings this AM

Post by gnat » Sat Nov 12, 2022 12:54 pm

Fuck you Schnelly! I blame you!

Took it out today as I had a longer errand to run and I don't remember the last time it was driven. Traffic was especially shitty today, but it was 73 so I had the windows down. Half an hour in I get a whiff of burning oil and while it's never me, I always glance at the dash just in case. Today was apparently the just in case as I caught it creeping towards the 250 line :shock:

Turning on the heat and finally getting onto the highway helped and it dropped to the 0 of the 180. So not pucker inducing, but not right unless it's over 100 out. Did the trip back home without the heater on and it stayed in the 0 of the 180, but traffic wasn't as bad.

I suspect something is up with the fans. The first stop neither the front nor rear were running, nor did I hear them screaming when the temp was almost 250. At my second stop both front and rear were running hard. When I got home the front was running as I would expect for the temp, but the rear was off.

At my first stop I opened the engine bay and the heat pouring out was inline with it being close to overheating 10 minutes earlier. A bit of steam came from the oil filler when I opened it, but it looks nice and clean (so I don't suspect intermix). The coolant tank looked good too as did the coolant in it.

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FRUNKenstein
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Re: Weird temp gauge readings this AM

Post by FRUNKenstein » Sun Nov 13, 2022 6:42 am

gnat wrote: Sat Nov 12, 2022 12:54 pm Fuck you Schnelly! I blame you!

Took it out today as I had a longer errand to run and I don't remember the last time it was driven. Traffic was especially shitty today, but it was 73 so I had the windows down. Half an hour in I get a whiff of burning oil and while it's never me, I always glance at the dash just in case. Today was apparently the just in case as I caught it creeping towards the 250 line :shock:

Turning on the heat and finally getting onto the highway helped and it dropped to the 0 of the 180. So not pucker inducing, but not right unless it's over 100 out. Did the trip back home without the heater on and it stayed in the 0 of the 180, but traffic wasn't as bad.

I suspect something is up with the fans. The first stop neither the front nor rear were running, nor did I hear them screaming when the temp was almost 250. At my second stop both front and rear were running hard. When I got home the front was running as I would expect for the temp, but the rear was off.

At my first stop I opened the engine bay and the heat pouring out was inline with it being close to overheating 10 minutes earlier. A bit of steam came from the oil filler when I opened it, but it looks nice and clean (so I don't suspect intermix). The coolant tank looked good too as did the coolant in it.
That does sound like a stuck thermostat.

Or a bad ignition switch.

Or mice.
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02TX996Cab
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Re: Weird temp gauge readings this AM

Post by 02TX996Cab » Mon Nov 14, 2022 7:52 am

gnat wrote: Sat Nov 12, 2022 12:54 pm Fuck you Schnelly! I blame you!

Took it out today as I had a longer errand to run and I don't remember the last time it was driven. Traffic was especially shitty today, but it was 73 so I had the windows down. Half an hour in I get a whiff of burning oil and while it's never me, I always glance at the dash just in case. Today was apparently the just in case as I caught it creeping towards the 250 line :shock:

Turning on the heat and finally getting onto the highway helped and it dropped to the 0 of the 180. So not pucker inducing, but not right unless it's over 100 out. Did the trip back home without the heater on and it stayed in the 0 of the 180, but traffic wasn't as bad.

I suspect something is up with the fans. The first stop neither the front nor rear were running, nor did I hear them screaming when the temp was almost 250. At my second stop both front and rear were running hard. When I got home the front was running as I would expect for the temp, but the rear was off.

At my first stop I opened the engine bay and the heat pouring out was inline with it being close to overheating 10 minutes earlier. A bit of steam came from the oil filler when I opened it, but it looks nice and clean (so I don't suspect intermix). The coolant tank looked good too as did the coolant in it.
You may be onto something in respect of the sensors and/or switches which activate the radiator fans.

Those fans pretty much have to run when the car is stuck in slow-and-go, otherwise there is negligible airflow through the radiators and roasty-toasty water and oil soon follow. When the car's moving along nicely, airflow from the car's movement alone is sufficient to keep things cool (unless it's thermonuclear hot outside, in which case you'd probably be running the A/C which IIRC also kicks the fans on).
Proud owner of a Flat6-powered 2002 996 Cab, 2016 GT4, 2019 Ford F-150 "Country Cadillac", and 2005 Ford Focus (not so hot hatch) daily driver. And a Wright ZTO 52" to keep several acres of grass-like substance neat and tidy!

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5chn3ll
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Re: Weird temp gauge readings this AM

Post by 5chn3ll » Mon Nov 14, 2022 11:24 am

My 996 is running perfectly now that I shifted the bad mojo onto Gnat.

Thanks, man.

Understeer: You will hit the wall with the front end.
Oversteer: You will hit the wall with the rear end.
Horsepower: How hard you will hit the wall.
Torque: How far you will move the wall.

Gone hunting with Alec Baldwin and Dick Cheney. Back soon.

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Dr_Strangelove
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Re: Weird temp gauge readings this AM

Post by Dr_Strangelove » Mon Nov 14, 2022 11:34 am

LOL it was a trap, I knew it.


gnat how's your water pump turning these days?
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