my water temp indicator is acting up climbing randomly and peaking. I have done alot of reading tonight and it appears to be a common problem.
1. i have used the test function and at what appears to be running temp my water is all over the place anywhere from 85-93 that seems to be a large variance. But i was testing on highway then off small distances and with a/c on during high temps.
2. my secondary electric condenser fan is running fine i can hear it.
3. i have read about faulty temp sensors around the thermostat so i unpluged her and clean off the contacts.
4. my coolant appears to be old so i am going to flush tomorrow.
Also today was record highs up in mass 90's. Funny thing is that i was in Florida about a month ago (much hotter than new england and had no problems)
I fear that i may have a faulty cluster, and or thermostat (maybe but i understand they fail open am i wrong?)
Thanks in advance with any insight you may have on my current inconvenience. I will keep you guys up to date with any progress and temp readings now that i know how to use test mode.
Can someone tell me what the average running temps are? Does it matter where you live or should the thermostat work out the difference?
I have a new thermostat waiting to be put in but i am avoiding it due to lack of time i would much rather just flush the coolant.
Funny you should ask this. I posted essentially the same question arising in a different context last weekend and received no response. After some seriously deep searching in the archives of the board and some first-hand experimentation, I determined that 93C is about as hot as your Beast should get in, say, 85 degree weather and/or idling in an open garage for 5-10 minutes. 93C is the point at which my auxiliary fan kicked in. The secret menu test on the cluster showed the typical operating temp while in reasonably well-moving traffic with an ambient temperature around 80 degrees to average about 91C or 90C. This, I should point out, is with a two-speed Zionsville radiator and Spal electric fan setup, but posts on similar issues by board members over the years corroborate this.
Thus, I think the fluctuation you are experiencing is within the typical range. I will say that air pockets in the coolant can cause wild fluctuations in Ktemp, but are pretty easily (as least, in my limited experience) resolved by using the TIS venting technique, viz., ignition on position 2, heat on high, fan on relatively low, add coolant until appropriate level is hit (on a Zionsville expansion tank, about an inch below the mouth; on a stock expansion tank, up to the "cold" level, then crank engine and warm up to operating temp, turn off engine, allow to cool, then repeat until, when the engine is cool, no more coolant needs to be added. That eliminated the air pockets for me and stabilized my Ktemp pretty dramatically.
--Peter
__________________ The Beast
2001 E39 M5 LeMans Blue with Black/Blue Sport Interior and Titanium Trim, ESS Supercharger, RMS In-Plenum Intercooler, RMS Plenum Plates and "Shorty" Velocity Stacks, Dinan TBs and Headers, CNS Catback Exhaust, Evosport High-Flow Cats, Dinan 3.45 Differential, GC Coilovers (550 Front/325 Rear), Dinan Front and Rear Swaybars, Dinan Monoballs, Dinan Wheels (18 x 9 Front/18 x 9.5 Rear), Bridgestone RE050 RFTs (275 Front/285 Rear), UUC EVO3 SSK with DSSR, Voltphreaks VPR-S40P Endurance Battery (14 lbs.), Setrab 16-Row Oil Cooler, Dinan Under-Plenum Heat Exchanger Removal Kit, Vorsteiner Double-Sided CF Hood with Open Vents, CA CSL-Style CF Trunk Lid, Zionsville Super Duty Cooling System, OKD Plasma Ignition Coils and Plug Boots, Smoked Hella Tailights, Clear-Corner Hella Euro Headlights, CA ACS-Style CF Front Splitters, Custom Stereo Using Stock HU, PLX Digital Gauge, V1/S1 Mounted in UGDO Location, Recaro Sportster CS Seats, Schroth 4-Pt Street Harnesses, and Various Other Bits and Pieces
Coming Soon!
Stoptech "Trophy" Brakes, TC Designs Roll Bar, TC Designs Rear Sway Bar Brackets, Aquamist HFS-6 Meth Injection with Custom CF/Aluminum Trunk-Mounted Fuel Cell Designed by Howerton Engineering, XRP HS-79 Hosing, Rogue Stage 3 280mm Clutch with JB Racing LTW Flywheel, Dinan Differential Subframe Reinforcement and Dinan Foglight Deletion Kit.
When the Motor Blows
Balanced and Blueprinted S62
The Following 4 Users Say Thank You to herrubermensch For This Useful Post:
last weekend temps hit 80. Mild traffic and according to the secret menu my coolant reached 103 degrees i turned the heat on pulled off 20 min later and coolant was 87 degrees C.
So am i overheating?
My temp gauge is all over the place if i am on the highway it actually runs below the middle. And if i hit traffic she sky rockets.
Help. I have a thermostat should i replace it? I am busy lately and don't want to replace if not needed. I think i am going to head to the dealer tomorrow for a software update. I read in some other post that there is an update needed to make the aux electric fan run longer and under different parameters. I hope this solves the problem.
The temp range on mine stays below halfway in normal driving - my tech mentioned it's a good sign the thermostat's on the way out. If your's shoots high in traffic, then I'd highly recommend having it checked. It might be worth asking the dealer on your visit tomorrow what they'd charge to diagnose the thermostat for you.
The relatively small cost to have it diagnosed/fixed would FAR surpass the expense of having it overheat - you always read horror stories of the carnage from BMWs overheating...
last weekend temps hit 80. Mild traffic and according to the secret menu my coolant reached 103 degrees i turned the heat on pulled off 20 min later and coolant was 87 degrees C.
So am i overheating?
My temp gauge is all over the place if i am on the highway it actually runs below the middle. And if i hit traffic she sky rockets.
Help. I have a thermostat should i replace it? I am busy lately and don't want to replace if not needed. I think i am going to head to the dealer tomorrow for a software update. I read in some other post that there is an update needed to make the aux electric fan run longer and under different parameters. I hope this solves the problem.
Any one have sound advice i am all ears.
Regards
Robbery
Sounds to me like you definitely are overheating. My guess is it's the thermostat. Sorry for your trouble.
__________________ The Beast
2001 E39 M5 LeMans Blue with Black/Blue Sport Interior and Titanium Trim, ESS Supercharger, RMS In-Plenum Intercooler, RMS Plenum Plates and "Shorty" Velocity Stacks, Dinan TBs and Headers, CNS Catback Exhaust, Evosport High-Flow Cats, Dinan 3.45 Differential, GC Coilovers (550 Front/325 Rear), Dinan Front and Rear Swaybars, Dinan Monoballs, Dinan Wheels (18 x 9 Front/18 x 9.5 Rear), Bridgestone RE050 RFTs (275 Front/285 Rear), UUC EVO3 SSK with DSSR, Voltphreaks VPR-S40P Endurance Battery (14 lbs.), Setrab 16-Row Oil Cooler, Dinan Under-Plenum Heat Exchanger Removal Kit, Vorsteiner Double-Sided CF Hood with Open Vents, CA CSL-Style CF Trunk Lid, Zionsville Super Duty Cooling System, OKD Plasma Ignition Coils and Plug Boots, Smoked Hella Tailights, Clear-Corner Hella Euro Headlights, CA ACS-Style CF Front Splitters, Custom Stereo Using Stock HU, PLX Digital Gauge, V1/S1 Mounted in UGDO Location, Recaro Sportster CS Seats, Schroth 4-Pt Street Harnesses, and Various Other Bits and Pieces
Coming Soon!
Stoptech "Trophy" Brakes, TC Designs Roll Bar, TC Designs Rear Sway Bar Brackets, Aquamist HFS-6 Meth Injection with Custom CF/Aluminum Trunk-Mounted Fuel Cell Designed by Howerton Engineering, XRP HS-79 Hosing, Rogue Stage 3 280mm Clutch with JB Racing LTW Flywheel, Dinan Differential Subframe Reinforcement and Dinan Foglight Deletion Kit.
When the Motor Blows
Balanced and Blueprinted S62
Last edited by herrubermensch; 13th May 2009 at 06:14.
def a thermo issue. I had the same exact issue before and I tried replacing the temp sensor which fixed the problem for a short period and then it started happening again. I know that my car was not overheating because I could turn off the car and when started again everything would be fine. Does your SES light come on when it spikes?
I ordered my thermo from Pelican Parts and installed it myself in about 30 minutes. No problems after that and it has been about 4 months, Temp seems fine never even gets to the half way mark. Also my coolant is about 4 years old and still going. Next on the list is the coolant hoses and complete cooling system flush.
BMW of Fairfax wanted $1200 to replace (parts+labor) - told them to F-Off when I heard that.
BTW- if you plan on doing a coolant flush ......MAKE sure you use only BMW coolant (I purchased from local bmw stealer for about $27). Other coolants can cause damage as I was told.
Last edited by madbadmixmaster; 13th May 2009 at 17:22.
i am going out of my mind installing this thermostat. I have broken 3 o-rings. I feel as if i would have been better off using the old ones since they are already compressed and fit perfect. I re-used the old ones for the oil cooler pipe the smaller of the three.
I wish i could find the other old ones but i think i threw them away.
Anyways
I had 6 more o-rings overnighted to the stealership. I will pick them up in the morning and let you guys know if this solves my overheating issue.
i am going to try and freeze the o-rings so they have a tighter fit on the tubes and heat up the tubes so that they expand. It seams that the o-rings are too loose and are getting pinched and tearing.
i turned the heat on pulled off 20 min later and coolant was 87 degrees C. 
Linear Mode
