Water Pump

[Blue-S]

Originally Posted by JFP in PA

From the factory, the M96 coolant typically runs between 210-215F when the dash gauge indicates 180 (the dash gauge is both inaccurate and non linear in its function), measured by the actual sensor in the coolant, which is pretty accurate when temperature tested out of the car.

When you say the dash gauge indicates 180, where is the needle pointing? Is it straight up, between the "8" and the "0"? I contend that the tic mark above the "8" is the 180 degree position, and the common cruise position (straight up, between the 8 and the 0) is intended to indicate HOTTER than 180 degrees. The gauge is certainly non-linear, and was apparently not designed to provide a precise temperature indication. If they had used a more serious-looking font, maybe they could have placed the number markings in a centered position below each respective tic mark. Maybe they should have just left the numbers off of the gauge altogether...

[JFP in PA]

Originally Posted by Blue-S

When you say the dash gauge indicates 180, where is the needle pointing? Is it straight up, between the "8" and the "0"? I contend that the tic mark above the "8" is the 180 degree position, and the common cruise position (straight up, between the 8 and the 0) is intended to indicate HOTTER than 180 degrees. The gauge is certainly non-linear, and was apparently not designed to provide a precise temperature indication. If they had used a more serious-looking font, maybe they could have placed the number markings in a centered position below each respective tic mark. Maybe they should have just left the numbers off of the gauge altogether...

Typically, we use the middle of the “8” as our reference point, and when the needle is there, the coolant is 210-215F; go past that and it gets even hotter, often reaching 225F by the time it is over the “0”. Because of the non linearity of the gauge, the relationship of position to actual temp is very misleading……

[pk2]

JPA_PA

Yup you do, Your a "CARB state", California has special status, its sets it's own standards, other states can choose between weak Fed standards and tough CA standards. PA and others follow CA. Lucky us lucky you. Unfortunately with the motor totally re-tuned for the blower, I barrrrrely squeaked by ...at idle no less!?!

A water to oil cooler makes them (the fluids) the same temp and that is 220-210, O.K. Why does my oil appear to be 188f. If you read my methodology & you get the logic, I think it's pretty sound. If you got a better method, let me know. Punch holes in mine. I don't care as long as the the numbers add up.

Funny thing though, I suppose if I already had a 160 thermostat (or 140 (?)), oil at 188f might be just about right and we could all go home. (Gotta get a good read on the coolant temp I guess.)


Regards, PK

BTWx2. Porsche has "a' hole in the thermostat, quaint. We just kept drilling till it worked right. 3 or 4 holes I think was the magic number. Did take longer to warm up though.

[JFP in PA]

Originally Posted by pk2

JPA_PA

A water to oil cooler makes them (the fluids) the same temp and that is 220-210, O.K. Why does my oil appear to be 188f. If you read my methodology & you get the logic, I think it's pretty sound. If you got a better method, let me know. Punch holes in mine. I don't care as long as the the numbers add up.

The problem is your methodology; you are not measuring the actual temperature of the flowing oil, you are measuring the outside metal of the sump using and indirect (non contact) method…………..there is no way your oil is circulating at 188F if you are running the OEM stat……………The M96’s coolant is pulling heat out of the oil once the engine is up to operating temperature, the oil typically is running 20-30F higher than the coolant…………………….

[Blue-S]

I will have to drive my 2000 "S" this evening and look at how the HVAC control panel diagnostic mode display for coolant temp compares with the needle position on the gauge. I should look at oil temp, too. Right now, ambient temp is in the neighborhood of 100 degrees in the inland areas of Southern California.

Here's the procedure for putting the HVAC panel in diagnostic mode:

Originally Posted by Lil bastard

On '97-'00 cars, you can access the diagnostics by holding the recirc and Air ↑ buttons for about 5 sec. Now you're in the diagnostic mode. The + - buttons allow you to scroll through the 36 different codes. The center button switches the display (left) from the code # and the actual value. To exit diagnostic mode, press Auto.

0c - ERL
1c - Oil temp
2c - Cabin temp as measured from the sensor mounted at the side of the dash.
3c - Outside temp - from AC air inlet
4c - Outside temp from ambient temp sensor on front grill (continuous)
5c - Outside temp feed from OBC display (5 sec. sampling and hold when stationary)
6c - Coolant temp
7c - Footwell discharge temp
8c - Sun sensor
9c - Sun sensor
10c - Cabin fan speed
11c - Cabin fan voltage
12c - Temp mix flap - 1=Cold, 100 = Hot
13c - Temp mix flap position
14c - Central flap cmmnd.
15c - Central flap position
16c - Footwell/defrost flap cmmnd.
17c - footwell/defrost position
18c - Recirc valve cmmnd - 1=Off, 100 = On
19c - Recirc valve position
20c - Vehicle speed in KPH, 1 sec. sampling, actual speed - no safety margin
21c - Engine RPM (hundreds) - 1 sec. sampling
22c - ??
23c - ??
24c - Display panel illum. voltage
25c - ??
26c - ??
27c - ??
28c - Fan speed
29c - ??
30c - Engine run time in sec. (255 max.)
31c - timing counter
32c - Display test
33c - Sftwr. ver.
34c - ??
35c - Outside temp from inlet sensor post filter
36c - Temp.

This unit is built by audi and the codes marked ?? have to do with different applications.

[pk2]

Blue_s.

Let me know what you find. I think I have that setup too but quite frankly, I never saw much of interest. Looks like you have though. Be nice to see some alternative numbers.

Only a hundred in Corona eh? It was 97 the day I did my test, about as hot as it's been, I live about 40 mi. south west of you. Figured at least 110 further inland.

Regards, PK

[ddb]

Originally Posted by Blue-S

I will have to drive my 2000 "S" this evening and look at how the HVAC control panel diagnostic mode display for coolant temp compares with the needle position on the gauge. I should look at oil temp, too.:

After recently installing a new water pump, 160F thermostat and new coolant in my 2000 2.7 I've been monitoring my coolant temperatures. With ambient temperatures in the mid-eighties and speeds in the 70 MPH range I'm running between 80-85C (176-185F). When I slow down or stop in traffic the temperature quickly rises to 95-99C (203-210F). I haven't cleaned my radiators in 5 years so I assume they aren't ideal. I haven't yet looked at oil temperatures but will on the next outing.

Curious to see what you are running with your S.

ddb

[cnavarro]

That's typical. The only way to keep the coolant at the cruise temp is to make the fans come on earlier. There's a thread on the 996 forums at Renntech on how to do the mod:

http://www.renntech.org/forums/index.php?showtopic=28093&st=0&p=148785&#entry148785

I plan on doing this mod to our Boxster myself as I see the very high trigger point for the fans as the real limiting factor.

[pk2]

Originally Posted by ddb

After recently installing a new water pump, 160F thermostat ...traffic the temperature quickly rises to 95-99C (203-210F). I haven't cleaned my radiators in 5 years so I assume they aren't ideal. I haven't yet looked at oil temperatures but will on the next outing.

Curious to see what you are running with your S.

ddb

DB, your fans aren't turning on very early. Mine come on within a minuet or 2 of hitting traffic. Once It''s warmed up, for what it's worth, the needle doesn't move much.

Don't know what your using for coolant, pretty sure it's not your prob but, your ready for a change. Might consider something like a quality version of GM.s Dex cool. Most of us traitors use Xerex dex-cool (compatible), about 1/5th the price of Porches exclusive juice and chemically identical where it counts (no silica or phosphates).

You probably knew all that already. If not, don't trust me, do some research. That's how I figured it out. It may still be controversial, so is the current issue at hand though.

Regards, PK

[pk2]

Originally Posted by JFP in PA

The problem is your methodology; you are not measuring the actual temperature of the flowing oil, you are measuring the outside metal of the sump using and indirect (non contact) method…………..there is no way your oil is circulating at 188F if you are running the OEM stat……………The M96’s coolant is pulling heat out of the oil once the engine is up to operating temperature, the oil typically is running 20-30F higher than the coolant…………………….

JFP in PA,

Working on a rebuttal. Have dyslexia but good. Takes forever to write something legible.

You make some good points but I think I have you on a few. To one point, you might look-up "digital laser pyrometer" on Wikipedia or wiki-answers (for simple answer).

Regards, PK

[JFP in PA]

Originally Posted by pk2

JFP in PA,

To one point, you might look-up "digital laser pyrometer" on Wikipedia or wiki-answers (for simple answer).

Regards, PK

Actually, as I already own two of them, a look up is not required, I know how they work, and their level of accuracy..................

[pk2]

Originally Posted by JFP in PA

Actually, as I already own two of them, a look up is not required,

Ya I guess not, ... perfect. You just saved me about an hour and a half trying to explain and key in what it's all about.

So, with this one, Ive measured quite a few different materials (including my head, including aluminum) and from different distances in different ambient environments etc. pretty accurately (used a standard scientific thermometer to verify a few). At the Lab I've seen them take pretty precise measurements at at least 1400 degrees. The only thing I can't measure is flame.

Since all it it sees is infared (IR), not the material or you or me, and the IR is all the same no matter where it comes from, and all it does is measure the intensity iradience) of the IR. Why do you think it can't accurately read the temp of this particular aluminum alloy of the sump?

Listen, I really appreciate you humoring me and sticking around. I think I just have one more thing that doesn't quite compute for me, and then I'll leave you alone.

It's sounding like this may be a genuine good thing.

Regards, PK