» Site Navigation | | » Recent Threads | | | ![](http://www.318ti.org/forum/clear.gif) | ![Reply](http://www.318ti.org/forum/images/buttons/reply.gif) | ![Share/Bookmark](http://static.addtoany.com/buttons/share_save_171_16.png) | 04-10-2012, 10:04 PM | #1 | Member Join Date: Oct 2009 Location: Louisiana Posts: 56 | Instruments lead to questions I have gotten myself a bluetooth OBD monitor that plugs into the port by the driver's left knee. Really shows a bunch of things I never knew and I am still poking around with the software (Torque on an Android tablet) Short term fuel trim data is quite interesting. One question already - my cooling water temp runs 98 -101 C at all times,on the low end of that range when the A/C is on, on the 100-101 end once warmed up and A/C off. Is that correct, the proper range? Seems I recall the thermostat being a much lower number but cannot lay hands on spec just now. My thermostat is practically brand new, replaced last fall when I did the radiator and hoses so I doubt that is problem. Clearly temp drops when fan kicks in on high with A/C so maybe running right at 100 all the time is correct? RAS | | | 04-10-2012, 11:44 PM | #2 | Senior Member Join Date: Oct 2008 Location: Los Angeles, CA Posts: 1,464 | Assuming your car is an OBD-II M44, the stock thermostat spec. is 95*C. There are, however, any number of things that could cause it to run hotter, including: air in the system, deteriorated water pump impeller, clogged radiator, clogged water jackets in the head/block, etc. If the temp. is noticeably fluxuating when the A/C kicks on and off, something isn't quite right. Does the temp needle noticeably move as well, or is it just on your OBD monitor? | | | 04-10-2012, 11:49 PM | #3 | Senior Member Join Date: Jul 2009 Location: MD/PA/DC Posts: 1,629 | Normal operating temperature is 12*F over the temperature of the thermostat IIRC. These things are designed to run hot. __________________ No more ti. | | | 04-11-2012, 01:04 AM | #4 | Member Join Date: Oct 2009 Location: Louisiana Posts: 56 | instruments and temps This is a 98 M44 OBD II. I do not see any real temp needle movement when the a/c kicks on, a very slight (1/4 needle width?) downward shift. I doubt I have a clogged radiator, as it is practically new, and if it is supposed to run at 12F above thermostat then I am almost dead on that at highest reading, just a little lower (12 f above 95 C is ~ 102C) Maybe 98-101 is just dead normal. Is there some reference for 12F above the thermostat spec? RAS Last edited by ryszardsh; 04-11-2012 at 01:05 AM. Reason: typo | | | 04-11-2012, 01:19 AM | #5 | Senior Member Join Date: Jun 2003 Location: Greenville, SC Posts: 9,356 | Quote: Originally Posted by ryszardsh I do not see any real temp needle movement when the a/c kicks on, a very slight (1/4 needle width?) downward shift. | You won't. Since the E36, water temp gauges are useless. I can be on the track at WOT in 95 degree weather and the needle is dead center. Then take my E30 where the needle actually moves up and down slightly whether I'm sitting or moving. __________________ ...steven BMW CCA #146825 1996 BMW 328ti • 2003 MINI Cooper S • 2016 M235i www.bmwcca.org | | | 04-11-2012, 04:08 PM | #6 | Senior Member Join Date: Jun 2003 Location: Halethorpe, MD Posts: 1,028 | Mine runs consistently in the 185 to 195 degree Fahrenheit range. | | | 04-11-2012, 09:31 PM | #7 | Member Join Date: Mar 2012 Location: iowa Posts: 90 | You're temp is fine. The reason for a thermostat is to aid in heating up the motor faster. So when the coolant is cooler the thermo is closed allowing the coolant in the block to heat up when it reaches temp the thermo opens and allows it to travel through the radiator. If the coolant only got to 95 degrees the temp the thermo opened at it would constantly be opening and closing. So they design them to open slighly cooler than what the engine should run at. Now the cooling fans are hooked up to another temp sensor and turn on and off to cool the coolant, they really only run in town as there's enough airflow at hwy speed. However when you turn the a/c the fans kick in to cool the condenser in front of the radiator. This also cools the coolant slightly. Bottom line, you're good. Cool toy though isn't it. | | | ![Reply](http://www.318ti.org/forum/images/buttons/reply.gif) | Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | | Posting Rules | You may not post new threads You may not post replies You may not post attachments You may not edit your posts HTML code is Off | | | |