Normal operating levels

I am somewhat newer to the 996 scene, being that I only have a couple thousand miles under the belt. What are the common operating levels for oil pressure, temp, coolant temp, etc. Maybe it is just do to the extreme Vegas heat, but the last couple days, the car doesn't seem to be running as it should. Last 2 days, especially on the way home (5pm and 110-113� outside), the coolant temp seemed to be rising. The oil pressure seems a bit low. Battery voltage looks ok, but the meter I have on my phone plugged in is showing 12.5V, which would be low. Idle is sitting at 750 RPM. Here is a where everything is sitting as I got to work this morning. Again, coolant temps look high, oil pressure looks low. 2000 911 C2 Cab w/ manual transmission. As you can see, just shy of 97k miles. Things I know have been done recently: New battery - 3 weeks ago Oil/Filter Change - Mobile1 0W-40 Syntheic - last night - this was rather dirty, but I didn't see any metal or foreign pieces in the filter Transmission oil drained and filled - last night What would cause the low voltage? Only accessories plugged in are Valentine 1 and my cell phone What to look for with the cooling system? Level looks fine. I plan on flushing this over the weekend as I don't know when it was done last. Oil pressure - I see the sending units are a common failure, along with the pressure relief valve. Could something with the low voltage and higher temps be causing this too? Ideas to look into tonight, this weekend, etc... Thanks![

Since the coolant temp is high, both of your coolant fans could be running on the "High" setting. That could explain the lower voltage. What is the voltage reading at cold start? It should be close to 14v. In any case, you should first verify if BOTH of your coolant fans are working in both "low" and "high" settings with no obstructions to the air flow. You can feel the air flow if you place you hand on the ground just a few inches in front of the front tires. At cold start, turn on the a/c and both fans should be on the "low" setting. When the coolant temp is very high, both fans should be ON high. With 0w-40 and high coolant temp, 0.8bar oil pressure may not be out-of-line.

The oil pressure seems fine for warmed up and idling. The temp is not out of line considering the ambient temperature. The voltage seems low - you should have your alternator tested. Edit: Or just listen to Ahsai

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^^This^^ Ahsai right on as usual... Any strange noises, ticks, tocks etc???

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I will check this out today. Was considering going to a different viscosity oil, but already had bought the 0W-40. With this heat, I run 20W-50 in my motorcycles. Would that be an acceptable choice for the 911, at least until it drops below 100� regularly? No strange noises. Feels and sounds great. But wasn't sure about the temps and such or if that should be expected with these cars and the Vegas heat waves.

Nothing there bothers me... the temp is still touching the 0 in the 180 - so that's okay... the oil pressure is fine given the heat. The voltage - I just had my alternator fail - it becomes apparent quick. As you're driving (and running air, fans, stereo) the voltage needle continued to drop. Short version - if you haven't actually put the car on charge over the last 3 days and it's still starting fine - your alternator is likely fine as well. I've run Mobil 15W 50 in my track car in the summer....

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No notice of the voltage fluctuations, but not really been watching for any. No charger, but daily driven. No notice of hard starts.

Got home and checked the voltage and was 13.1 at idle. Dropped to 13 when the fans kicked on. Had it tested and the voltage regulator shows bad

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Make sure the grounds on the car are clean. There is a strap from the engine to the body and from the negative battery terminal to the body. A poor connection will kill the voltage regulator over time. The previous owner of my car sold it to me at a discount because he had gone through two alternators and a battery and it made him very frustrated. His Indy didn't figure it out. Within minutes after trailering the car home, I found the connection from the negative battery terminal to the body to be significantly corroded. I cleaned it up, installed a new alternator, and my car runs great. No further alternator related issues in the past year and a half.

The shown voltage looks perfectly fine to me. Orherwise measure the voltage directly on the aternator. I had the alternator refurbished lately and after cold start and driving when the battery is recharged the voltage drops from around 14V a bit to 13.5V. With fans on high, mine drops sometimes to 12.9-13.0. Nothing to worry about I suppose. Would not be bad to check the ground. Higher temperatures in the engine bay mean als higher resistances which result in higher voltage drops.

Your temps and oil pressure behave as they should for a car with 100k miles. As water temp increases, the oil pressure drops. I don�t believe 15w or 20w cold is a �certified winter� weight for these cars, but 5w-50 is. You will probably gain oil pressure switching to 50, I know I did. Was this is around town driving with stop and go? Or was it highway. If highway, I would check into cleaning the front radiators. If around town, this might be normal. Here�s my advice for temps: borrow a Durametric from someone or buy an ODBII device and use a smartphone app to pulls temps from the ECU. I�ve found that the white line way past zero is where my fans will kick on, not before (unless the AC is on), and that�s because the ECU is recording temps 10F lower than my gauge on the dash (or the HVAC hack display).

Regarding the voltages, don't forget the alternator-starter Y-cable. They tend to go bad and have been redesigned several times. I had low voltage and replaced my voltage regulator first, but had voltage drop to as low as 12.4 at some points. Changed the Y-cable and immediately got back up to 14v without fans, 13.5 with.

OP: In your dash pic did you have the AC on? Reason I ask is my car pops the idle up to @850 with AC on. Yours appears to be a bit under 800. Not sure if that would be significant or not. Ahsai is the man...btw!

Hmmm... so the voltage regulator. Which is correct? only item I found on sunset porsche in terms of voltage regulator and this is on pelicanparts.

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I have an OBDII attachment, going to check and see if it gives me real time numbers this morning

I got my regulator from Pelicanparts and I think it's a Bosch unit ~$40

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Same on my car. And since RPMs go up, so does oil pressure. The other thing to note is that my oil pressure gauge is sometimes off by 1/2 point at turn-on. So I sometimes get 5 bar on cold start, sometimes 5.5 bar. Same with hot pressure (1.0 bar or 1.5 bar) at idle. Even my speedo is off by 2.5 mph

I view the oil pressure sending unit as kind of a "go" or "no go" type of thing. Currently mine pegs at 5 all the time, so it needs changing. I really don't think they are calibrated by any stretch of the imagination. My speedo is off by 4 mph consistently, but I mostly drive by RPM anyway.

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that's what I am thinking. also looks like one is at the battery (sunset) and the other at alternator (pelican). i don't take them as 100% accurate, but the gauges have to be somewhat close, right?

so apparently when I bought the OBD tool last year, it is just a code reader in essence. wouldn't give me real time info. but the coolant didn't seem to get as high today, needle sitting in middle of or edge of the 0 in 180. Previously was pushing the 3/4 mark.

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So I assume you probed the back of the alternator and got lower than expected reading? BTW, if it's truly the alternator, another option is to use the 997 alternator ($~270) Bosch AL0815N, which is a brand new and not a reman'ed unit.

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If you have an Android phone, you can buy a $10 Bluetooth OBDII dongle and paired that with the "Torque Pro" app.

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there is also an inexpensive WiFi version that works with iOS devices. I use one with my iPad and the �OBD fusion� app. Works great!

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i checked the voltage at the battery at that point. when it was reading lower than it should, i took it to have the battery, alternator tested and that came up with a Voltage Regulator failure. i will have to look into this. i purchased this one previously for another car. doesn't look like it will do anything in detail with the Porsche. i wonder if it will connect via another app...

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I have an iPhone and bought this one: Car Bluetooth OBD2 Code Readers, TONWON OBDII Bluetooth Scan Tool ELM327 Car Diagn... https://www.amazon.com/dp/B06XTP3HDG/ref=cm_sw_r_sms_c_api_i_tR5wBbF5C6CA4 Shows the same temp reading as Durametric, except only Durametric can pull oil temps.

Installed the new voltage regulator. So far, the voltage is back up. Will see tomorrow how the oil pressure and coolant temps respond.

It really is advisable to remove the front bumper and split the 4 x rads to clean out the debris. You will be amazed at the amount of crap that forces itself between the A/C condenser and coolant rads…... There's plenty of "how to's " describing the job - very worth while after 100k miles!

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Its on the list of to do's. Got a busy week and working next weekend, so hopefully after that.

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What are you able to read with your apps?

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I wouldn�t wait for 100k miles.

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Lots of items, such as air intake temp, absolutely throttle position, derived HP and torque, MPH, RPM, ECTS (engine coolant temperature sensor), absolute manifold pressure, fuel economy, long and short term fuel trim, fuel rail pressure gauge, mass airflow, secondary air status, intake timing, all the O2 sensor data with temps and voltage, cat temp,