DIY: (E9x) M3 Thermostat Replacement

Thik · 04-25-2021, 07:29 AM

So the dealership is recommending that I replace the thermostat housing, but not the thermostat? If 3-4 hours of labour is involved, do you think it's worth might as well replace the thermostat too?

NeverL8 · 04-25-2021, 11:43 AM

Quote:

Originally Posted by Thik

So the dealership is recommending that I replace the thermostat housing, but not the thermostat? If 3-4 hours of labour is involved, do you think it's worth might as well replace the thermostat too?

Why do you need to replace thermostat housing? Do you have any codes, problems with the car?

Assimilator1 · 04-25-2021, 03:07 PM

Quote:

Originally Posted by Thik

So the dealership is recommending that I replace the thermostat housing, but not the thermostat? If 3-4 hours of labour is involved, do you think it's worth might as well replace the thermostat too?

I think you and the dealer are getting crossed wires, I bet what they actually meant is to change the housing and the t/stat as one unit, which is unnecessary, unless the housing has been damaged somehow??
Are you sure they meant changing the housing only?

Anyway, assuming the housing is damaged, unless the t/stat is really quite new, it would be bonkers not to change it whilst you're there! So yes, definitely worthwhile changing it too.

Thik · 04-26-2021, 06:19 AM

Quote:

Originally Posted by Assimilator1

I think you and the dealer are getting crossed wires, I bet what they actually meant is to change the housing and the t/stat as one unit, which is unnecessary, unless the housing has been damaged somehow??
Are you sure they meant changing the housing only?

Anyway, assuming the housing is damaged, unless the t/stat is really quite new, it would be bonkers not to change it whilst you're there! So yes, definitely worthwhile changing it too.

I used Carly and got the code 002859, Thermostat monitoring. I figured the dealer scanned the same code. Yes, the part they quoted is 11-53-7-838-480, the thermostat housing, but not the actual thermostat. They said there was a small coolant leak.

Even if the thermostat was working fine, still sounds like it's worth replacing since they quoted 4.7 hours of labour to replace the housing.

Assimilator1 · 04-26-2021, 01:20 PM

Lol, they're having a laugh with that time!
I posted earlier with how long it took me the 1st and 2nd time (I cut an o-ring

), 1st time I took it slow, and was sorting out clips for the liner and undertray, as well as doing a full coolant drain (from the rad), that took 3-3.5 hrs.
After finding a coolant leak at 3.45 pm (and the workshop closing at 5.30!), I rushed it (didn't drain off coolant, aside from header tank) and had it done by ~5.10! And on reassembling it the 2nd time (the plenum) my 7mm socket and UJ fell of my driver handle (after only the 2nd clip luckily) and I had to take the plenum off again! So I probably would've done it ~10mins quicker if that hadn't happened.

I'd get a quote from a BMW inde if I were you, I bet they'll quote a lower time and price!

[edit] Your car isn't supercharged, right?

e92m3sf · 07-14-2021, 02:16 PM

Hey thanks for the DIY, I followed it 2 years ago to replace my thermostat.

Since then, I've gotten 3 new codes yesterday:

Fault code: 002AF9 Coolant temperature sensor
Fault code: 002B59 Coolant thermostat monitoring
Fault code: 002AFD Relative time plausibility

Does this look like the temp. sensor?
My car is taking longer than usual warming up to normal temps (only symptoms so far) and an increased emissions code

Assimilator1 · 07-14-2021, 03:15 PM

Hmm, in my experience working on other cars, usually when a temp sensor fails it will go open circuit and so just fail completely, rather than give consistently low readings, but that isn't 100% sure by any means!

Is the heater taking longer to warm up too?
Where are you located? ('location ca' doesn't mean anything to me I'm afraid).

If you're in the summer, and despite the warmer ambient temps it's still taking longer than usual to blow hot then it would seem to be the thermostat's gone again! No idea why, unless it was a cheap one/unknown brand?

Btw, you could do a resistance test of the CTS to see if it's in spec, that should confirm or eliminate it then.

e92m3sf · 08-02-2021, 02:20 PM

Quote:

Originally Posted by Assimilator1

Hmm, in my experience working on other cars, usually when a temp sensor fails it will go open circuit and so just fail completely, rather than give consistently low readings, but that isn't 100% sure by any means!

Is the heater taking longer to warm up too?
Where are you located? ('location ca' doesn't mean anything to me I'm afraid).

If you're in the summer, and despite the warmer ambient temps it's still taking longer than usual to blow hot then it would seem to be the thermostat's gone again! No idea why, unless it was a cheap one/unknown brand?

Btw, you could do a resistance test of the CTS to see if it's in spec, that should confirm or eliminate it then.

Sorry, I just saw this reply now.
I'm located in California so the weather is pretty good here.

I've been driving the car since the problem and the overheating problem never came back. I had an emissions CEL on for about a couple days when I scanned those codes but that light went away as well, although the fault codes are still active on Carly.

My plan is to change the coolant sensor when my part comes in.

Would that be an advisable first step? If not what do you suggest?

Thanks

Assimilator1 · 08-02-2021, 02:33 PM

Overheating? You never mentioned that in your last post.
You said it was taking longer to warm up, which is it?

If I had no signs of the engine running cold, or taking ages to heat up, my 1st step would be to measure the resistance of the CTS. Or with the engine stone cold (e.g laid up over night), either with Carly or via the hidden menu see what temperature the CTS is giving and whether that matches up with ambient temperature.
Also using Carly, see how long it takes for the coolant to get fully warmed up when driving it (~85C, whatever that is in F

).

cloumeM · 02-01-2022, 03:57 PM

Thank you OP for this DIY!!! I got a code scanned by AutoZone today indicating the faulty thermostat (no other codes). After reading through this thread, I decided to replace the sensor as well. All parts ordered (ECS Tstat replacement kit, 4 extra o-rings, and sensor). I also plan to pick up the pump to syphon the coolant from the overflow reservoir. Most definitely be incorporating multiple tips and recommendations from everyone done this DIY replacement. For that, thank you very much!!! Should I come across anything unique (hopefully nothing bad), I'll be sure to return and share with this group.

BTW, I have some goodies on their way involving the plenum removal, this is somewhat timely, and I plan to knock them all out in one session.

OldenburgerM3 · 03-16-2022, 03:21 PM

thanks for this!

e90Dawg08 · 04-30-2022, 07:48 PM

First off, thank you for the awesome DIY. I just tackled this and was able to siphon out about a gallon of coolant, inspect my water pump (saw it was good) and replaced the thermostat + sensor + o-rings.

I am a bit stuck though and looking for some help.

I went to put my plenum back on and it seems 2 of the TB rubber gaskets got squished from me over tightening the clamps. Now I'm struggling to get the plenum to sit down as far as it should. I also saw people recommend testing for coolant leaks with the plenum off. So, I have 2 questions:

1) Once I fill the coolant back up, is there anything I need to install with the plenum removed in order to test? I'm assuming I should just have the car on in the garage and follow the coolant filling instructions with high heat for a few minutes? Just makes me nervous having the sensor off that plugs into the plenum.

2) In order to get the plenum to sit correctly, is it ok to use silicone lube on the gaskets? I have 2 of them with small pinches and I have a feeling it's getting caught on those with no lube. Or what would be the appropriate lubricant to use on them?

Thanks for the help! Again, awesome DIY!

cloumeM · 05-02-2022, 02:21 PM

Quote:

Originally Posted by e90Dawg08

First off, thank you for the awesome DIY. I just tackled this and was able to siphon out about a gallon of coolant, inspect my water pump (saw it was good) and replaced the thermostat + sensor + o-rings.

I am a bit stuck though and looking for some help.

I went to put my plenum back on and it seems 2 of the TB rubber gaskets got squished from me over tightening the clamps. Now I'm struggling to get the plenum to sit down as far as it should. I also saw people recommend testing for coolant leaks with the plenum off. So, I have 2 questions:

1) Once I fill the coolant back up, is there anything I need to install with the plenum removed in order to test? I'm assuming I should just have the car on in the garage and follow the coolant filling instructions with high heat for a few minutes? Just makes me nervous having the sensor off that plugs into the plenum.

2) In order to get the plenum to sit correctly, is it ok to use silicone lube on the gaskets? I have 2 of them with small pinches and I have a feeling it's getting caught on those with no lube. Or what would be the appropriate lubricant to use on them?

Thanks for the help! Again, awesome DIY!

I heard about the TB rubber gaskets cracking issue and the best solution was to replace it/them. What stinks is that I also heard the price of these rubber gaskets went up significantly (around $25 or more each now???). Good luck with this weekend project!

TX · 05-02-2022, 02:30 PM

Quote:

Originally Posted by cloumeM

I heard about the TB rubber gaskets cracking issue and the best solution was to replace it/them. What stinks is that I also heard the price of these rubber gaskets went up significantly (around $25 or more each now???). Good luck with this weekend project!

try $40 each.

Bimmerworld has them for a few bucks less:
https://www.bimmerworld.com/Rubber-I...V8-E9X-M3.html

cloumeM · 05-02-2022, 10:48 PM

Quote:

Originally Posted by TX

try $40 each.

Bimmerworld has them for a few bucks less:
https://www.bimmerworld.com/Rubber-I...V8-E9X-M3.html

Yikes!

Assimilator1 · 05-03-2022, 02:16 PM

That's bonkers!

Might be cheaper to have specialists make them??

TX · 05-03-2022, 02:25 PM

Quote:

Originally Posted by Assimilator1

That's bonkers!

Might be cheaper to have specialists make them??

I don’t see how. You’re unlikely to find someone who can tool up production for a one off item such as this for anywhere close to this price or quality.

Assimilator1 · 05-06-2022, 05:40 AM

Could an appropriate rubber be 3d printed??

us722 · 05-03-2023, 02:50 PM

Anyone has a link to 100% silicone lube they're using on t-stat/ o-rings to have it slide in perfect and not cause issues?

Secondly, on coolant mix... can I just use pre mixed Prestone that applies to all cars e.g. this guy I have sitting in the garage (I believe its green but mixes with other coolants).

https://ca.prestone.com/product/pres...-ready-to-use/

nick3753 · 05-05-2023, 04:18 PM

Quote:

Originally Posted by us722

Anyone has a link to 100% silicone lube they're using on t-stat/ o-rings to have it slide in perfect and not cause issues?

Secondly, on coolant mix... can I just use pre mixed Prestone that applies to all cars e.g. this guy I have sitting in the garage (I believe its green but mixes with other coolants).

https://ca.prestone.com/product/pres...-ready-to-use/

I don’t know about which silicone lube, but definitely do not use that coolant. Get the BMW specific coolant or Pentosin Pentofrost blue coolant. You can also use coolant as your lube.

Assimilator1 · 05-06-2023, 11:25 AM

Why not use that coolant?

cloumeM · 06-21-2023, 10:19 PM

I just did my t-stat amd sensor this week. Only drained the colant from the reservoir, placed a thick towel under the three connecting tubes (one small one to reservoir and two large tubes), and disconnected the them. Spilled about half cup of coolant from the housing. No mess at all. Used the silicone lub spray which I picked up from Walmart ($7.50?). This was so much easier job than I had anticipated. Refilled the reservoir with just about 1 gallon (pretty much what I pumped out from the reservoir). Drove around, waited for the engine to cool down, checked the coolant level, and refilled half cup of the coolant mix. All good!

04-25-2021, 07:29 AM	#155
Thik First Lieutenant 140 Rep 371 Posts Drives: 2010 Space Grey E92 M3 6spd Join Date: Jan 2013 Location: Toronto iTrader: (0)	So the dealership is recommending that I replace the thermostat housing, but not the thermostat? If 3-4 hours of labour is involved, do you think it's worth might as well replace the thermostat too? __________________ Check out my YouTube channel chronicling all the driving fun in my E92 M3!
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04-26-2021, 01:20 PM	#159
Assimilator1 Major 589 Rep 1,025 Posts Drives: BMW M3 e92 08 & 330d e90 10 Join Date: Sep 2019 Location: UK, Surrey iTrader: (0) Garage List 2010 BMW 330d [8.00] 2008 BMW M3 [0.00]	Lol, they're having a laugh with that time! I posted earlier with how long it took me the 1st and 2nd time (I cut an o-ring ), 1st time I took it slow, and was sorting out clips for the liner and undertray, as well as doing a full coolant drain (from the rad), that took 3-3.5 hrs. After finding a coolant leak at 3.45 pm (and the workshop closing at 5.30!), I rushed it (didn't drain off coolant, aside from header tank) and had it done by ~5.10! And on reassembling it the 2nd time (the plenum) my 7mm socket and UJ fell of my driver handle (after only the 2nd clip luckily) and I had to take the plenum off again! So I probably would've done it ~10mins quicker if that hadn't happened. I'd get a quote from a BMW inde if I were you, I bet they'll quote a lower time and price! [edit] Your car isn't supercharged, right? __________________ . Oil analysis for finding wearing rod bearings?. Collation of oil analysis reports with some rod bearing photos for the M3's S65. My categorisation of pulled rod bearings in the rod bearing condition thread. My updated 'Blown engines' list. Last edited by Assimilator1; 04-26-2021 at 01:27 PM..
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07-14-2021, 02:16 PM	#160
e92m3sf Private 4 Rep 61 Posts Drives: e92 m3 Join Date: Nov 2016 Location: ca iTrader: (0)	Hey thanks for the DIY, I followed it 2 years ago to replace my thermostat. Since then, I've gotten 3 new codes yesterday: Fault code: 002AF9 Coolant temperature sensor Fault code: 002B59 Coolant thermostat monitoring Fault code: 002AFD Relative time plausibility Does this look like the temp. sensor? My car is taking longer than usual warming up to normal temps (only symptoms so far) and an increased emissions code
	Appreciate 0 Quote

07-14-2021, 03:15 PM	#161
Assimilator1 Major 589 Rep 1,025 Posts Drives: BMW M3 e92 08 & 330d e90 10 Join Date: Sep 2019 Location: UK, Surrey iTrader: (0) Garage List 2010 BMW 330d [8.00] 2008 BMW M3 [0.00]	Hmm, in my experience working on other cars, usually when a temp sensor fails it will go open circuit and so just fail completely, rather than give consistently low readings, but that isn't 100% sure by any means! Is the heater taking longer to warm up too? Where are you located? ('location ca' doesn't mean anything to me I'm afraid). If you're in the summer, and despite the warmer ambient temps it's still taking longer than usual to blow hot then it would seem to be the thermostat's gone again! No idea why, unless it was a cheap one/unknown brand? Btw, you could do a resistance test of the CTS to see if it's in spec, that should confirm or eliminate it then. __________________ . Oil analysis for finding wearing rod bearings?. Collation of oil analysis reports with some rod bearing photos for the M3's S65. My categorisation of pulled rod bearings in the rod bearing condition thread. My updated 'Blown engines' list.
	Appreciate 0 Quote

08-02-2021, 02:33 PM	#163
Assimilator1 Major 589 Rep 1,025 Posts Drives: BMW M3 e92 08 & 330d e90 10 Join Date: Sep 2019 Location: UK, Surrey iTrader: (0) Garage List 2010 BMW 330d [8.00] 2008 BMW M3 [0.00]	Overheating? You never mentioned that in your last post. You said it was taking longer to warm up, which is it? If I had no signs of the engine running cold, or taking ages to heat up, my 1st step would be to measure the resistance of the CTS. Or with the engine stone cold (e.g laid up over night), either with Carly or via the hidden menu see what temperature the CTS is giving and whether that matches up with ambient temperature. Also using Carly, see how long it takes for the coolant to get fully warmed up when driving it (~85C, whatever that is in F ). __________________ . Oil analysis for finding wearing rod bearings?. Collation of oil analysis reports with some rod bearing photos for the M3's S65. My categorisation of pulled rod bearings in the rod bearing condition thread. My updated 'Blown engines' list.
	Appreciate 0 Quote

02-01-2022, 03:57 PM	#164
cloumeM Lieutenant 166 Rep 477 Posts Drives: BMW e93 M3 Join Date: Sep 2021 Location: St. Louis, MO iTrader: (7)	Thank you OP for this DIY!!! I got a code scanned by AutoZone today indicating the faulty thermostat (no other codes). After reading through this thread, I decided to replace the sensor as well. All parts ordered (ECS Tstat replacement kit, 4 extra o-rings, and sensor). I also plan to pick up the pump to syphon the coolant from the overflow reservoir. Most definitely be incorporating multiple tips and recommendations from everyone done this DIY replacement. For that, thank you very much!!! Should I come across anything unique (hopefully nothing bad), I'll be sure to return and share with this group. BTW, I have some goodies on their way involving the plenum removal, this is somewhat timely, and I plan to knock them all out in one session.
	Appreciate 0 Quote

03-16-2022, 03:21 PM	#165
OldenburgerM3 Private First Class 72 Rep 183 Posts Drives: 2011 Jet Black M3 Coupe Join Date: Feb 2011 Location: TX iTrader: (0)	thanks for this!
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04-30-2022, 07:48 PM	#166
e90Dawg08 Enlisted Member 42 Rep 40 Posts Drives: 08 e90 M3 Join Date: Jun 2021 Location: SC iTrader: (0)	First off, thank you for the awesome DIY. I just tackled this and was able to siphon out about a gallon of coolant, inspect my water pump (saw it was good) and replaced the thermostat + sensor + o-rings. I am a bit stuck though and looking for some help. I went to put my plenum back on and it seems 2 of the TB rubber gaskets got squished from me over tightening the clamps. Now I'm struggling to get the plenum to sit down as far as it should. I also saw people recommend testing for coolant leaks with the plenum off. So, I have 2 questions: 1) Once I fill the coolant back up, is there anything I need to install with the plenum removed in order to test? I'm assuming I should just have the car on in the garage and follow the coolant filling instructions with high heat for a few minutes? Just makes me nervous having the sensor off that plugs into the plenum. 2) In order to get the plenum to sit correctly, is it ok to use silicone lube on the gaskets? I have 2 of them with small pinches and I have a feeling it's getting caught on those with no lube. Or what would be the appropriate lubricant to use on them? Thanks for the help! Again, awesome DIY!
	Appreciate 0 Quote

05-03-2022, 02:16 PM	#170
Assimilator1 Major 589 Rep 1,025 Posts Drives: BMW M3 e92 08 & 330d e90 10 Join Date: Sep 2019 Location: UK, Surrey iTrader: (0) Garage List 2010 BMW 330d [8.00] 2008 BMW M3 [0.00]	That's bonkers! Might be cheaper to have specialists make them?? __________________ . Oil analysis for finding wearing rod bearings?. Collation of oil analysis reports with some rod bearing photos for the M3's S65. My categorisation of pulled rod bearings in the rod bearing condition thread. My updated 'Blown engines' list.
	Appreciate 0 Quote

05-06-2022, 05:40 AM	#172
Assimilator1 Major 589 Rep 1,025 Posts Drives: BMW M3 e92 08 & 330d e90 10 Join Date: Sep 2019 Location: UK, Surrey iTrader: (0) Garage List 2010 BMW 330d [8.00] 2008 BMW M3 [0.00]	Could an appropriate rubber be 3d printed?? __________________ . Oil analysis for finding wearing rod bearings?. Collation of oil analysis reports with some rod bearing photos for the M3's S65. My categorisation of pulled rod bearings in the rod bearing condition thread. My updated 'Blown engines' list.
	Appreciate 0 Quote

05-03-2023, 02:50 PM	#173
us722 Private 16 Rep 97 Posts Drives: m3 Join Date: Nov 2017 Location: canada iTrader: (0)	Anyone has a link to 100% silicone lube they're using on t-stat/ o-rings to have it slide in perfect and not cause issues? Secondly, on coolant mix... can I just use pre mixed Prestone that applies to all cars e.g. this guy I have sitting in the garage (I believe its green but mixes with other coolants). https://ca.prestone.com/product/pres...-ready-to-use/
	Appreciate 0 Quote

05-06-2023, 11:25 AM	#175
Assimilator1 Major 589 Rep 1,025 Posts Drives: BMW M3 e92 08 & 330d e90 10 Join Date: Sep 2019 Location: UK, Surrey iTrader: (0) Garage List 2010 BMW 330d [8.00] 2008 BMW M3 [0.00]	Why not use that coolant? __________________ . Oil analysis for finding wearing rod bearings?. Collation of oil analysis reports with some rod bearing photos for the M3's S65. My categorisation of pulled rod bearings in the rod bearing condition thread. My updated 'Blown engines' list.
	Appreciate 0 Quote

06-21-2023, 10:19 PM	#176
cloumeM Lieutenant 166 Rep 477 Posts Drives: BMW e93 M3 Join Date: Sep 2021 Location: St. Louis, MO iTrader: (7)	I just did my t-stat amd sensor this week. Only drained the colant from the reservoir, placed a thick towel under the three connecting tubes (one small one to reservoir and two large tubes), and disconnected the them. Spilled about half cup of coolant from the housing. No mess at all. Used the silicone lub spray which I picked up from Walmart ($7.50?). This was so much easier job than I had anticipated. Refilled the reservoir with just about 1 gallon (pretty much what I pumped out from the reservoir). Drove around, waited for the engine to cool down, checked the coolant level, and refilled half cup of the coolant mix. All good!
	Appreciate 0 Quote