[Searay55555]

Hi Guys,

Cooling System Problems.
’12 335is E93

I’m lost here. I’m on the 3rd WP, replaced about 20K miles ago. I have experienced NO problem with it until recently changing a hose. On 6/19/22, I discovered a pin hole in the short hose that runs from the WP to the TS. Since I couldn’t get one for a couple days, I cut it down about ½” (this is where the hole was) and put the same one on until I could get the new one and had time to install it. I replaced, refilled, and drove the car for about 15 minutes. No problems. The next day, I drove it over an hour at freeway speeds, and then another :20 home from work. Zero problems. The next day, 6/21 on the way to work, it overheated. I assume the WP wasn’t working. I had to let it cool down several times, but eventually made it the few remaining miles to work. After work, I drove it home with NO problems Back to normal – everything was fine. 6/21 – 7/4 it drove normally, no problems. Yesterday, July 4th, I installed the new hose, refilled, and ran the bleed procedure (well, attempted to but I’m not sure if it ever worked). I ran the car for 30 minutes with no problems – I kept an eye on the water temp, and watched it rise until the TS let the coolant flow and regulate to around 85 degrees C.

This morning, I started out to work again thinking everything was fine. Same exact problem as 2 weeks ago. I overheated and had to limp my way the rest of the 3 miles over an hour. I went out at lunch and started the car, opened the reservoir to see if water was pouring in from the overflow line. Nothing was flowing, so it appears the WP isn’t pumping. Also, no check engine light is on.

Does anyone have any idea what the hell is happening? This is only happening after I flush and fill.

TIA, Kevin

[Bmw1939]

In a case like this maybe get a professional diagnosis then do the job yourself.

[Searay55555]

It’s looking list that. I’m running out of patience on the side of the road in Phoenix in the summer. Still exhibiting the same problem. It’s like the water pump needs a jump start.

[Dataguy]

Did you pull codes?
You can check water pump flow by pulling the cap on the reservoir and running the bleed procedure and monitoring the flow. Also, is the fan coming on? I have a '12 335is also and I'm overheating at idle, posted a day ago.

[Searay55555]

I didn’t pull codes but there is no check engine light on. There is also no flow. Water pump is not functioning at the moment. Maybe an air lock. Fan is working fine. The Stealership has it now. I just don’t have time to play with it anymore. Will report back when I have findings. Overheating at idle doesn’t sound good. I’ve never had that, even in 115° temps.

[def328]

Watching this with interest. I'm having the same issues except Carly is reporting code 2E83, leading back to the WP. I replaced it (and the TS) last August and ECS was reluctant to send a new pump out under warranty, but they did. And since the radiator is 13 years old now, I opted to get a new one and will hopefully get everything replaced over the course of this weekend.

Failing that, I'm not sure what the culprit could be other than some part of the cooling system sucking air in (but not expelling coolant).

[Dataguy]

I just posted the solution to my overheating at idle issue: faulty Coolant temp sensor... also no codes.

If you never used them, try FCP Euro out of CT. They have lifetime warranty on nearly everything they sell. You only pay shipping. About every two years I replace my plugs and coils under this program and all it costs me is the shipping to return the old parts. FYI I replaced the Brakes and Rotors on this same program... talk about cutting down the cost of ownership

[ryan stewart]

Wondering if youre bleeding. If youre stationary with the car off and the hood up you should be able to tell the bleed procedure is running, you can hear the water running/sloshing as it gets pretty aggressive. You can even open the bottle and see it pouring from the overflow line, etc.

[Searay55555]

I tried to bleed, but the pump didn’t actuate. It’s not pumping at all now. Dealer said there is a stored code. Not sure when that was from as I never cleared codes. Of course they want to replace the WP that has 2 years and 20K mikes on it.

[tcphoto]

Why would you replace the WP three times? The part would have a warranty whether you had it installed or DIY. It sounds like you need an Indy to take a look or a dealer as a last resort.

[Searay55555]

Original failed at around 70K miles. Replaced with one that sprang a leak at around 90K miles. On the third one, which seemed fine until this problem. It was a Gates so it should still be good. Still waiting for the official word from the dealer. It was the tech that said it was recommended replacement in the video he sent.

[Searay55555]

Hahaha, $2400 to replace the WP. Can’t make this stuff up.

[tcphoto]

I paid an Indy just under $1K for a new water pump, thermostat and coolant flush nearly four years ago. Are you telling me that the pandemic has more than doubled the price?

[Searay55555]

I’m telling you TESLA seems like the right answer here. This is insanity. I’m ready to just go pick it up, throw it in the garage, and rent a car.

I did find out that there were 2 faults within the last 20 miles or so. Maybe the wire harness connection? I’m just not sure how it works one day, and the next day it doesn’t. Doesn’t make sense.

[ryan stewart]

Electrical problems have that all the time. A weak ground can come and go, or a broken wire can barely make connections.

My hatch wires to the diversity antenna would come and go from vibration, opening the hatchet etc. The wore was only held together by the jacket and could touch not touch, etc

[Searay55555]

I’m probably going to pick the car up and just try to figure it out myself. Anyone know how to check to see if the electrical connection is the problem? Now I wish I had saved the old pump that ran but just leaked. I would think plugging a new one in while loose would tell me.

[tcphoto]

Nothing beats getting under it and inspecting the harness and connectors.

[TheMidnightNarwhal]

Originally Posted by Searay55555

I didn’t pull codes but there is no check engine light on. There is also no flow. Water pump is not functioning at the moment. Maybe an air lock. Fan is working fine. The Stealership has it now. I just don’t have time to play with it anymore. Will report back when I have findings. Overheating at idle doesn’t sound good. I’ve never had that, even in 115° temps.

Pulling codes is always number 1 step. Even if no CEL, sometimes the modules will have codes in them that don't trigger CEL.

But yeah, let us know if you get the answer curious!

EDIT: Just read rest of the thread shoot, yeah, dealer diagnostics usually entail replace and see if it works.... . Idk if you had the chance to even inspect anything yet but like tcphoto says, checking the wires would be next thing to check for sure.

Also you said you tried bleed procedure but nothing worked, can you confirm you were doing the procedure correctly?

[Searay55555]

Yes, there were 2 recent faults showing up in the dealer scan.

Dealer diagnostics seem lazy and rapey, and it seems you are right here.

I checked the wire harness when I replaced the hose. All seemed fine, and it worked right after for a half hour of running.

Yes, I’m pretty sure I ran the bleed procedure correctly, as there just aren’t that many steps. What I missed was, I didn’t know you could actually hear it working so I never checked to see if it actually was. So, honestly I’m not sure if it ran or not.

[ryan stewart]

I'd run it again to be sure. Do the procedure and then put your head near the upper hose or bottle for 30 seconds. It varies speed but occasionally hits warp speed and you'd definitely hear a whooshing noise.

And it does that for a loong time, that is why the recommend having a tender hooked up.

[TheMidnightNarwhal]

Yeah now I'm curious to, if the bleed procedure comes on at all. Like Ryan says try again and hear for it. On the 3rd or 4th cycle of the 12 minute bleed procedure, it spins pretty much full speed whoosh and very audible.

Just to make sure you're doing it right:
- Ignition on
- Manual HVAC
- Full temp on both zones
- Fan on lowest setting
- Mash gas pedal ~ 10s, should start hearing it as it starts

[Searay55555]

Okay, thanks I’ll try it again. However, I’m not sure it’s going to work as the pump doesn’t seem to be pumping anything right now. I should be seeing fluid return, via the overflow and there is nothing coming out, leading me to believe it’s not running. The procedure you mentioned is exactly what I performed.