12-16-2020, 10:42 AM | #1 |
Captain
556
Rep 906
Posts |
Slow coolant leak, EGR cooler?
I was poking around my engine bay and noticed my coolant expansion tank was near the low mark, even with a warm driven engine. I looked though my records and realized that
Dec 2019: Last dealer service, expansion tank full (overfilled beyond top half of the tank) Nov 2020: Coolant level seemed normal on cold engine, level just at the high mark. Today: Coolant level at low mark warm or cold engine So in about a year, the coolant level dropped from the overfilled to low, and it dropped from normal to low in less than a month. The last time I touched the system was during my PH test in late October, but all I did was extract, measure, and return to tank. I inspected all coolant hoses, radiators, and connections, no visible signs of leaks. The dealer did the EGR cooler recall back in Sept 2019 and it checked out fine. I dont have any other symptoms of a EGR cooler issue, no faults, no abnormal smells. What are the chances the EGR cooler is causing the leak?
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World |
12-16-2020, 11:49 AM | #2 |
Brigadier General
4016
Rep 3,540
Posts
Drives: 328d Wagon, M2 Comp, i4 eD35
Join Date: Sep 2016
Location: Bay Area, CA
|
Mine is similar. Had EGR cooler check, no issues/leaks, checked hoses/fittings and didn't see anything, but coolant level drops slowly over time.
__________________
-328d Wagon Build Log (with helpful reference links)
-My YouTube Channel for some of the best DIYs and in depth information Please don't PM me for suspension recommendations unless interested in paid private consultations. |
Appreciate
0
|
12-23-2020, 10:31 AM | #3 |
Mini Cooper, Present F15 Owner
27
Rep 90
Posts |
Speaking of leaks, anyone want to hazard a guess as to what was dripping down on my wheel chock from this particular location? That's the right front tire of my 2015 328d Touring... Kinda looks like a "slushy" or "slurpy". Nobody in my household gets those, though!
|
Appreciate
0
|
12-24-2020, 09:43 AM | #4 | |
Private First Class
107
Rep 123
Posts |
Quote:
Get an engine oil analysis and look at the sodium value. Ours started to increase at just past 50k while coolant loss was minimal at 1 qt over 10k miles. We had a steady/slow coolant loss until past 90k when it we lost 1qt in only 1500miles. Sodium made a big jump at the same point. If you engine oil shows more than 1ppm per 1000miles I would suspect the cooler leak has started. Ours jumped from <1ppm to ~4ppm per 1000 miles when the leak started. Sodium doubled when the coolant leak rate increased past 90k. Wear metals started to rise at that point too. Sodium returned to normal once the cooler was replaced. |
|
Appreciate
0
|
12-24-2020, 09:51 AM | #5 | |
Lieutenant Colonel
1410
Rep 1,803
Posts |
Quote:
|
|
Appreciate
0
|
12-24-2020, 05:57 PM | #6 | ||
Captain
556
Rep 906
Posts |
Quote:
Quote:
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World |
||
Appreciate
0
|
12-25-2020, 06:31 PM | #7 |
Private First Class
107
Rep 123
Posts |
I did multiple pressure test from the first loss of coolant till it went into the dealer for the recall. 20psig/20min, never had any pressure drop. All were performed when engine cold. I suspect the leak opens up when hot, closes up when cold with the help of exhaust gas deposits.
|
Appreciate
0
|
12-28-2020, 08:55 AM | #8 |
New Member
5
Rep 19
Posts |
This weekend my low coolant level warning came on. I added 5 cups of coolant to bring it up to the tank seam.
I had the EGR changed at the dealer and shortly after the low coolant warning came on. I found that the small black screw head vent thingy was loose, allowing vapor to escape. I tightened it up and top off the coolant, that was 25k miles ago. I'm right under 200k miles and have not replaced the waterpump yet. No leaks can be seen. I really hope its not the new EGR cooler |
Appreciate
0
|
01-03-2021, 08:47 PM | #9 |
Second Lieutenant
54
Rep 203
Posts |
It take only about 20 minutes to check the EGR cooler for leakage.
Just remove the inlet from the cooler to the intake, and look into the cooler for damp gooey soot. if the cooler is ok, you'll just see dry soot. The BMW inspection TSB: https://static.nhtsa.gov/odi/rcl/201...8V755-1757.pdf I lost coolant a couple times and didn't look at my cooler till after the intake had holes burned through it. BMW did repair everything at no cost. |
Appreciate
0
|
01-04-2021, 11:46 PM | #10 |
New Member
8
Rep 11
Posts |
These things can leak from the SCR (Urea) metering unit. There are two soft coolant lines going to it with two quick release joints to hard pipe. Very close to hot exhaust and subject to a lot of vibration. When they dribble, coolant will drop onto the hot aluminum belly pan that is directly beneath the exhaust pipe resulting in no puddle, no smell, just the mysterious loss of coolant and some slight residual markings if you ever pull the pan to access the meter. It's bolted on with security torx so they really didn't want you to be looking up there, lol.
|
Appreciate
0
|
01-04-2021, 11:51 PM | #11 | |
New Member
8
Rep 11
Posts |
Quote:
|
|
Appreciate
0
|
01-05-2021, 01:44 PM | #12 |
Mini Cooper, Present F15 Owner
27
Rep 90
Posts |
That's exactly what this looks like! I have had no recurrences so I'm stymied with what it was.
EGR recall was done earlier last year and I would have thought it would have worked all its magic long before I found this! I'll just have to monitor to see if it happens again. So far I have no other indications of trouble. |
Appreciate
0
|
01-05-2021, 01:48 PM | #13 |
Mini Cooper, Present F15 Owner
27
Rep 90
Posts |
I do have headlight washers, but haven't added any strange colored fluid. I liked the rat-eating popsicles the best, but all of our wildlife is either much smaller or much larger than a rat!
|
Appreciate
0
|
07-09-2021, 11:31 AM | #14 |
Captain
556
Rep 906
Posts |
It's been about 5500 miles since the coolant bottle was last topped off and I think there is a drop in the coolant level. Ended up topping off the tank with Zerex G48
Coolant level before: 35588 on the odo, cold engine, topped off by dealer Coolant level after: 41142 on the odo, cold engine
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World |
Appreciate
0
|
08-19-2021, 04:42 PM | #15 | |
Captain
556
Rep 906
Posts |
Blackstone just returned me my UOA, sample had about 8K miles on it. Oil was LiquiMoly TopTec 4600. Sodium levels were at 57, which they said was higher than normal and might be a sign of a slow coolant leak.
Quote:
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World Last edited by capt_slow; 08-19-2021 at 07:07 PM.. Reason: Added UOA text |
|
Appreciate
0
|
08-19-2021, 04:54 PM | #16 |
Private First Class
107
Rep 123
Posts |
If there was a straight leak of coolant into the oil then potassium values should be higher too. If they are in single digits I'd lean heavily toward the EGR cooler leaking.
|
Appreciate
0
|
09-18-2021, 03:35 PM | #17 |
Captain
556
Rep 906
Posts |
Coolant level: 46821 on the odo, cold engine
It's been a little over 5K since the last check and the coolant bottle is pretty much back to where it was before. Topped up about 1 Cup of coolant to bring it back to the seam.
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World |
Appreciate
0
|
10-05-2021, 12:53 PM | #18 |
Registered
0
Rep 1
Posts |
New to the forum. My car was doing the same thing every 5000-7000 miles I would have to add about 1/2 quart to 1 quart coolant. I had the recall done and they ndf the vechile. About 2 mouth ago the cooler failed and holes in the intake. If you don't know where the coolant is going there's probably a small leak in the cooler when the car gets hot.
|
Appreciate
0
|
11-30-2021, 08:03 PM | #19 |
Captain
556
Rep 906
Posts |
Update: (another) EGR Cooler Recall
Finally brought the F31 to the dealer to have them look at the dropping coolant issue. To my surprise, there is a open safety recall for the EGR Cooler, this is a new one as it shows up on the dealer system but not the online BMW recall database.
My car passed inspection on the first EGR Cooler recall (18V-755), but it seems like the car is now getting a redesigned part. Parts are still not available yet, but nice to know I might be getting my slow coolant drop problem fixed. https://www.consumerreports.org/car-...k-a7622678572/
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World |
12-01-2021, 08:24 AM | #20 | |
Lieutenant Colonel
1410
Rep 1,803
Posts |
Quote:
__________________
-2014 328d Wagon, 8HP. Self-tuned, 270hp/430ft-lbs.
-2019 M2 Competition MT, Alpine White. Self-tuned 560hp -2016 Mini Cooper S, MT. Many plans. Others: -E36 328is. 2000 Z3 Roady. 2003 VW Jetta TDI Manual. Estoril Z3M Coupe. |
|
Appreciate
0
|
12-01-2021, 10:39 AM | #21 | |
Brigadier General
4016
Rep 3,540
Posts
Drives: 328d Wagon, M2 Comp, i4 eD35
Join Date: Sep 2016
Location: Bay Area, CA
|
Quote:
__________________
-328d Wagon Build Log (with helpful reference links)
-My YouTube Channel for some of the best DIYs and in depth information Please don't PM me for suspension recommendations unless interested in paid private consultations. |
|
Appreciate
0
|
12-01-2021, 06:45 PM | #22 | |
Captain
556
Rep 906
Posts |
Quote:
Dealer did look at the dropping coolant levels. Car passed another pressure test and they diagnosed the leak as coming from the connector in the expansion tank. At this point, I'm getting a new EGR cooler regardless, so I'm ok with this.
__________________
2017 328d xDrive Sports Wagon: Estoril Blue, Black Sensatec, M-Sport Pkg
2020 i3 Rex: Capparis White, Giga World |
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|