Water temp calibration IS inaccurate in basemap - updated calibration within

Old 01-13-2010, 01:15 AM
  #1  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default Water temp calibration IS inaccurate in basemap - updated calibration within

My car has an oversized alloy radiator with the undertray and very good ducting. It also has a coolant reroute, brand new water pump and all coolant hoses. I'm running straight distilled water in the cooling system which is only a week old.

The Adaptronic logs my coolant temp going up to 108C/226.5F for short periods after giving it a short squirt, but I have yet to do a track day. I was just wondering if you thought this was accurate? It seems a bit on the high side. The stock gauge doesn't seem to move past the 11-11.30 position, and it's not dumping water into the overflow tank. The intake temps can be up to 70C/158F post intercooler; it's been pretty warm here lately.

Has anyone calibrated their coolant sensors? I checked the Adaptronic values with those in the Mazda workshop manual and they are within spec but the range is huge.

Cheers

Last edited by timk; 01-17-2010 at 12:39 AM.
timk is offline  
Old 01-13-2010, 01:22 AM
  #2  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,821
Total Cats: 3,481
Default

A lot of the maps here have the values that Stein put on his when he calibrated his sensor with a thermometer/etc.
The rest are the values that Travis provided from his car as well as some others.

So the values are definitely not spot on. If you CAN calibrate yours (meaning you have all the necessary equipment and time) I think it would be a great idea to calibrate it.


That said, my car used to get as high as 120c in the summer after some WOT. Now in the cooler temps and with the reroute/new thermostat it never goes above 100-105.
18psi is offline  
Old 01-13-2010, 01:27 AM
  #3  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

Unfortunately I'm not really geared up for it. I could possibly send a spare temp sender to Adaptronic if they can do it, unless one of the engineering guys on here can save us the hassle?
timk is offline  
Old 01-13-2010, 08:48 AM
  #4  
Elite Member
iTrader: (46)
 
Stein's Avatar
 
Join Date: Dec 2007
Location: Nebraska
Posts: 4,729
Total Cats: 166
Default

Originally Posted by 18psi
A lot of the maps here have the values that Stein put on his when he calibrated his sensor with a thermometer/etc.
The rest are the values that Travis provided from his car as well as some others.
I don't think that I did anything with the water, just used the values supplied. I did do my own IAT, but then after someone posted up the original GM values, I changed mine to that.
Stein is offline  
Old 01-13-2010, 01:22 PM
  #5  
Junior Member
iTrader: (1)
 
bellwilliam's Avatar
 
Join Date: Aug 2007
Posts: 384
Total Cats: 12
Default

op. since you have a coolant reroute. did you bleed it correctly ? it is very difficult to get it right. 2 ways of doing it right.
1. use a vacuum pump
2. lift the rear of the car up, run the engine, wait till you see a big bubble (radiator will go empty). add water. then you do the same with rear lowered, front raised.

the temp you described is exactly the same as ones that's not bled correctly.
bellwilliam is offline  
Old 01-14-2010, 04:40 AM
  #6  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

Thanks for the tips about bleeding, you're probably right about my car. When I burped the cooling system I did it with the radiator as the highest point (had the front of the car on the higher bit of my driveway) but I haven't done this the other way around. Out of interest do you know where the air gets trapped when the car is this way?
timk is offline  
Old 01-14-2010, 06:05 AM
  #7  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

I should also mention that oil temps don't appear to go over 90C (freeway driving with A/C on) where the coolant temps often sit over 100C. I'll try the coolant burp on the weekend.
timk is offline  
Old 01-14-2010, 11:02 AM
  #8  
Elite Member
 
JasonC SBB's Avatar
 
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
Default

If someone could tell me the pullup resistance value in the Adap, and a known good curve from another ECU, it shouldn't be hard to figure out the whole curve of voltage vs. temperature. Doesn't EasyTherm from the MS guys do this?
JasonC SBB is offline  
Old 01-14-2010, 11:18 AM
  #9  
Junior Member
iTrader: (1)
 
bellwilliam's Avatar
 
Join Date: Aug 2007
Posts: 384
Total Cats: 12
Default

Originally Posted by saboteur
I should also mention that oil temps don't appear to go over 90C (freeway driving with A/C on) where the coolant temps often sit over 100C. I'll try the coolant burp on the weekend.
yeap, that sounds like an air pocket. again, it is very difficult to burp it out, even doing rear jack, then front jack thing. it takes a few try.

easiest way is to find a shop with vacuum pump. 10 minutes job.
bellwilliam is offline  
Old 01-14-2010, 11:23 AM
  #10  
Elite Member
 
JasonC SBB's Avatar
 
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
Default

Massaging the upper hose vigorously while idling does it.
JasonC SBB is offline  
Old 01-14-2010, 01:53 PM
  #11  
Elite Member
iTrader: (9)
 
TravisR's Avatar
 
Join Date: Jun 2008
Location: Houston, TX
Posts: 1,547
Total Cats: 13
Default

Careful not to go below 25inhg. I found this out when venturi vacuuming my coolant system. Radiator fluid boils pretty good down there. "Jeee, that's an AWFUL LOT OF AIR IN THERE" I kept thinking. Which then turned into... WAIT that's not air, that's boiling liquid.


Originally Posted by bellwilliam
yeap, that sounds like an air pocket. again, it is very difficult to burp it out, even doing rear jack, then front jack thing. it takes a few try.

easiest way is to find a shop with vacuum pump. 10 minutes job.
TravisR is offline  
Old 01-14-2010, 04:22 PM
  #12  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

Originally Posted by JasonC SBB
Massaging the upper hose vigorously while idling does it.
That sounds like lots of fun but I'm using the M-Tuned hose with reinforcing anti-kink spring so you can't squeeze it!!

I'll let you know how things turn out over the weekend.
timk is offline  
Old 01-14-2010, 04:31 PM
  #13  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

Originally Posted by JasonC SBB
If someone could tell me the pullup resistance value in the Adap, and a known good curve from another ECU, it shouldn't be hard to figure out the whole curve of voltage vs. temperature. Doesn't EasyTherm from the MS guys do this?
As per this thread, the Adaptronic runs a 4.7k pullup resistor for coolant and air temp:
V10Q Firmware upgrade (Also V10R beta)- 37050 errors after Flashit Verify

His info seems reliable.

Don't know if this info is of any use:
http://forum.miata.net/vb/showthread.php?t=338768

Cheers

Last edited by timk; 01-14-2010 at 06:25 PM.
timk is offline  
Old 01-15-2010, 12:00 AM
  #14  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

I got these numbers from cjernigan and then worked out the ADC values:

Temp, Resistance, ADC value
0c 6000 2296
40c 1100 776
80c 320 261

The values aren't really matching up to those in the basemap so there's some inaccuracies somewhere. :(
timk is offline  
Old 01-15-2010, 10:04 PM
  #15  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

OK, I grabbed another 99 coolant temp sendor and did some testing. I boiled a saucepan of water and measured the resistance between pins A and B. I could get the resistance as low as 189 Ohms (I think it flashed at 188 at one stage but it was steady on 189).

189 Ohms converted to ADC is 158, the basemap has an ADC value of 180 in the 100C row. So according to my test, the Adaptronic will report the temp as being 108C when it is actually 100C.

Can someone else do this same test? Not sure how accurate my multimeter is, so I'd like confirmation.

Cheers
timk is offline  
Old 01-16-2010, 07:24 PM
  #16  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

Here is a graph I made (ADC values not resistance) showing the error margin comparing the basemap with the DIY values. I filled in the gaps using the Steinhart-Hart equation:



This equation is the same one used by EasyTherm for MegaSquirt, it seems to be very accurate.

I will post up a screenshot of the new settings soon. They should be a lot closer than the old basemap settings.

Last edited by timk; 01-17-2010 at 08:13 PM.
timk is offline  
Old 01-16-2010, 07:34 PM
  #17  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

This post is now redundant.

Last edited by timk; 01-17-2010 at 12:17 AM.
timk is offline  
Old 01-17-2010, 12:36 AM
  #18  
Senior Member
Thread Starter
 
timk's Avatar
 
Join Date: Dec 2004
Location: Brisbane, Australia
Posts: 1,278
Total Cats: 37
Default

Here's the final result:



Let me know how you go!

Cheers
timk is offline  
Old 01-17-2010, 08:55 AM
  #19  
Newb
 
bitrusty's Avatar
 
Join Date: Sep 2008
Posts: 14
Total Cats: 0
Default

frickn' legend!

this will help a LOT of ppl
bitrusty is offline  
Old 01-17-2010, 09:57 AM
  #20  
Junior Member
iTrader: (10)
 
sv650_ck's Avatar
 
Join Date: Jan 2007
Posts: 457
Total Cats: 3
Default

Originally Posted by saboteur
Nice work. Significant difference between 25 to 70. It looks like the fans will still kick on and off at roughly the same temps.
sv650_ck is offline  

Thread Tools
Search this Thread
Quick Reply: Water temp calibration IS inaccurate in basemap - updated calibration within



All times are GMT -4. The time now is 10:15 PM.