Low coolant level mystery. - E46Fanatics E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Go Back   E46Fanatics > E46 BMW > General E46 Forum

General E46 Forum
This is the place to get answers, opinions and everything you need related to your E46 (sedan, coupe, convertible and wagon) BMW!

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 11-11-2019, 10:58 AM   #1
Oldmactech
Registered User
 
Join Date: Mar 2012
Location: Atlanta
Posts: 156
My Ride: 325 i wagen
Low coolant level mystery.

Wifeís e46 wagon has a low coolant light that comes on shortly after switching to heat, goes off as heat is turned off. Swapped level sensors, no joy. Coolant level is correct. No signs of leaks. Temp is rock solid.

Likely going to do water pump soon will I need to replace coolant tank? Any thing I can test to find the source of the odd symptom?


Sent from my iPad using Tapatalk
Oldmactech is offline   Reply With Quote
Old 11-11-2019, 12:29 PM   #2
tcphoto
Registered User
 
Join Date: Sep 2009
Location: Madison, GA
Posts: 1,882
My Ride: E92 335 MT Coupe
I would try bleeding the system again, there are probably air bubbles in there and it should go away.
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
tcphoto is offline   Reply With Quote
Old 11-11-2019, 05:03 PM   #3
My325XI
Registered User
 
Join Date: Dec 2007
Location: Charlotte, NC
Posts: 1,088
My Ride: 03 325XI Sprt Prem
Year: 2003
Model: 325XI
Transmission: Manual
In my experience, the heat opens the heater core and more coolant flows there giving the low coolant warning. Check the coolant in the morning when it's cold and also bleed as well. That should solve the problem.

Sent from my SM-G920V using Tapatalk
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

2003 325XI 5-speed ZSP ZPP
My325XI is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-11-2019, 05:49 PM   #4
jmo69
Registered User
 
Join Date: Mar 2013
Location: Wisconsin
Posts: 5,207
My Ride: 03 325xi 98 328is
You don't have to change the tank when you do the pump If you bleed the system cold with the key in pos 2, the heat set to high and the fan on low the heater valve will be open and any air should bleed out. The heater valve should be open by default but it won't hurt to have the heater on. Putting the car on ramps always works for me.


Sent from my SM-G950U using Tapatalk
__________________
Alternative to expensive xi control arm bushings
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


Bad outer xi ball joint?
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

2003 325xi auto Stahlgrau

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

1998 328is 5sp
jmo69 is offline   Reply With Quote
Old 11-11-2019, 07:08 PM   #5
Oldmactech
Registered User
 
Join Date: Mar 2012
Location: Atlanta
Posts: 156
My Ride: 325 i wagen
Thanks, Iím curious, the cold bleed in key position 2 implies that there is a coolant pump between the tank and the firewall? My X5 has one, donít think this e46 does. Or, did I not get your point?


Sent from my iPad using Tapatalk
Oldmactech is offline   Reply With Quote
Old 11-12-2019, 12:00 AM   #6
jmo69
Registered User
 
Join Date: Mar 2013
Location: Wisconsin
Posts: 5,207
My Ride: 03 325xi 98 328is
There's no auxiliary pump on an e46, they just specify the key to be on with those settings. It's worked every time for me. Just slowly fill the tank with the bleed screw out till there's a solid stream of coolant coming out of it. The put the screw back in, remove the excess coolant from the tank, put the cap back on and start the car. Run it to temp and check for good heat, if it doesn't overheat during a test drive you should be good. Check the level daily when it's cold and adjust until it stabilizes.
__________________
Alternative to expensive xi control arm bushings
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


Bad outer xi ball joint?
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

2003 325xi auto Stahlgrau

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

1998 328is 5sp
jmo69 is offline   Reply With Quote
Old 11-12-2019, 03:10 AM   #7
Anticdubai
Registered User
 
Join Date: Sep 2019
Posts: 39
When bleeding, Switch climate control to heat so it will open heater valve and coolant will circulate trough heater core.
Anticdubai is offline   Reply With Quote
Old 11-12-2019, 11:30 AM   #8
Oldmactech
Registered User
 
Join Date: Mar 2012
Location: Atlanta
Posts: 156
My Ride: 325 i wagen
Ok, thanks for the clarification.


Sent from my iPad using Tapatalk
Oldmactech is offline   Reply With Quote
Old 11-13-2019, 01:06 AM   #9
jmo69
Registered User
 
Join Date: Mar 2013
Location: Wisconsin
Posts: 5,207
My Ride: 03 325xi 98 328is
Quote:
Originally Posted by Anticdubai View Post
When bleeding, Switch climate control to heat so it will open heater valve and coolant will circulate trough heater core.
I do that too, but there are a few people on here that claim the heater valve is open with the key off.
__________________
Alternative to expensive xi control arm bushings
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


Bad outer xi ball joint?
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

2003 325xi auto Stahlgrau

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

1998 328is 5sp
jmo69 is offline   Reply With Quote
Old 11-13-2019, 01:56 AM   #10
Anticdubai
Registered User
 
Join Date: Sep 2019
Posts: 39
Quote:
Originally Posted by jmo69 View Post
I do that too, but there are a few people on here that claim the heater valve is open with the key off.


Yes it opens when you off engine. And obviously closes as soon as you start engine, and remains closed till you switch heat on. So you bleed system and have to make sure there is no air stays in a heater core so you put climate to heat and it opens the valve.
Anticdubai is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON



All times are GMT -5. The time now is 01:35 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
(c) 1999 - VerticalScope Inc. All rights reserved.