[Jeremyxc]

Hey everyone,

First I'd like to thank the community on the nearly hundreds of pages of information on this topic. It's all be very helpful.

*2007 335i, 122,*** miles. manual

Now here is where I need some help.
Last week I was driving home on the highway and received a yellow thermostat warning, about one minute later I received the red signal and my car went into limp mode. (thank god I made it to a parking lot) I cut the car off for about 45 minutes and went to the gas station and bought distilled water. After the engine cooled I opened the reservoir and added some water, this is when I saw the water pump was doing absolutely nothing.

I then had my car towed back to my house and waited two days to completely replace the water pump and thermostat. I bought the water pump, thermostat and coolant directly from a bmw dealership. Following the F******* awesome DIY instructions on this site.

Here is where I messed up.

When refilling the coolant I didn't follow proper instructions when putting it in. I merely put a mixture of 50/50 coolant and water then let it run until I saw a steady stream coming from the water pump tube. I then shut my car off and proceeded about my day.

After that I have driven the car 5 times. Heat worked perfectly.
3 times highway 30-45 miles
2 times city 2-3 miles

I had no issues until suddenly yesterday driving through the city I again received the yellow warning light then red then limp. I was able to pull into a parking lot. I then "burped it" by releasing some pressure after it cooled down some by slightly opening the coolant reservoir lid. I then left it in the parking lot for 4 hours.

Doing research for two of the hours prompted me to come back and do the proper vent procedure. ( Car off. Power on. hold peddle down 10 sec.. 12 min to finish. sounds like washer machine.. I did hear the water pump come on). After doing this and checking my levels twice I then drove around the parking lot and received the yellow sign and red sign again. During this time the heat was blowing cold air still.

I again cut my car off until temp was cool and did research. After cooling I did a higher level burping procedure which involved opening the cap of the reservoir and revving the engine to around 4krpms for a few seconds and letting it back down. I observed 4-5 large air pockets coming from the coolant reservoir along with some coolant and water.
After that I began to drive the car around an empty parking lot for around 10-15 minutes. No lights or signals came on. After exiting the lot I got around 4 blocks and the yellow light came on. I then pulled into another lot and did more research and tried to use the bleeder valve to let out the remaining air for about 30 minutes, constantly checking the levels. At this time while slowing adding distilled water i can see it enter the reservoir and be pushed around by air coming from where the water pump hose would usually shoot out coolant.

After needed to sleep for work I left the car in the parking lot overnight and I'm staring out my office window at it trying to figure out how else I can try to fix it. I'm at a loss, if anyone can help please...

[Aptechguy]

Sounds like the water pump is on its way out

[BashShah]

Flush the fluid again....
3/4 drain by disconnecting at the heat exchanger.....next to the rad at the bottom.
In clip hose.....
Go buy BMW antifreeze, and distilled water From a drug store.
Mix 50/50.
Now put hose back on and refill.

Then purge sysyem ... Gas pedel down for 10 sec.
Then top off if need be, and purge again.

What I am saying is do 2 purge cycles

DN

[Jklad]

Originally Posted by DarkNemesis

Flush the fluid again....
3/4 drain by disconnecting at the heat exchanger.....next to the rad at the bottom.
In clip hose.....
Go buy BMW antifreeze, and distilled water From a drug store.
Mix 50/50.
Now put hose back on and refill.

Then purge sysyem ... Gas pedel down for 10 sec.
Then top off if need be, and purge again.

What I am saying is do 2 purge cycles

DN

+1. Follow the proper instructions.

Also, is the water level going down, or is there a leak? New wps have been failing recently, lots of posts where they cracked quickly after installation due to a defect or possibly incorrect bolts being used.

[Jeremyxc]

Originally Posted by DarkNemesis

Flush the fluid again....
3/4 drain by disconnecting at the heat exchanger.....next to the rad at the bottom.
In clip hose.....
Go buy BMW antifreeze, and distilled water From a drug store.
Mix 50/50.
Now put hose back on and refill.

Then purge sysyem ... Gas pedel down for 10 sec.
Then top off if need be, and purge again.

What I am saying is do 2 purge cycles

DN

I performed this exactly as stated here. And still had the issue of the overheating. I took it to the bmw dealership for a diagnostic and payed the 160

They are saying a few things, the most important being my BSD line is down and needs replacing. The parts are just 60 bucks, but they want 426 in labor charges. Is this something I can do myself? Not finding any DIY's on the site
Your guys input is greatly appreciate it.


( Been a little while, was out of town for christmas)

[BashShah]

BSD - Bit Serial Data interface line?.....at the battery I think....
How is that causing the over heating?

So you are not losing coolant.....like a leak....right?
When your car over heats, Is the fan running?
Is the water pump also running?
Are your hoses hot, is heat coming from the vents.....when turned on?

Is the electrical connection at the water pump OK?
Did you clear codes before or after water pump and tstat change?
What codes are currently in memory?....run a diagnostic?

DN

[catcher22]

[QUOTE=Jeremyxc;19073220]
I merely put a mixture of 50/50 coolant and water then let it run until I saw a steady stream coming from the water pump tube. I then shut my car off and proceeded about my day.
QUOTE]

Well first off props to you for replacing your waterpump and thermostat. From your write up, it sounds like something may have gone wrong with the coolant fill and bleed procedure, so I'd start there. I'm not quite understanding your quote above.

1) Do you mean you just filled the entire gallon 50/50 coolant first, then the rest with distilled water?

2) Or do you mean you put the mix in properly (premixed the coolant and distilled water first) and just filled it up and let the car run?

Either way, it looks to be something with the fill/bleed procedure. Try that procedure again as 1) it's the most likely issue, 2) it's the easiest troubleshooting procedure right now..lowest hanging fruit, and 3) the cheapest fix to try right now (few bucks for another gallon of coolant and distilled water).

[Efthreeoh]

I'd disconnect the battery for a half hour. Reconnect the battery. Do the correct bleeding procedure, which is to have the system completely closed when bleeding, then top off.

[PichaDis11]

Originally Posted by Efthreeoh

I'd disconnect the battery for a half hour. Reconnect the battery. Do the correct bleeding procedure, which is to have the system completely closed when bleeding, then top off.

Never understood this though I do it all the time. if the system is closed, where does the trapped air go??

[Efthreeoh]

Originally Posted by PichaDis11

Never understood this though I do it all the time. if the system is closed, where does the trapped air go??

It goes to the highest level of the cooling system, which is the top of the reservoir. When you open the reservoir, you top off the coolant to replace the volume of air that was trapped. That's why you fill the cooling system with the bleed screw open because that is where the air escapes from the head as you fill the cooling system. Then you close the cooling system completely (so it builds pressure when the pump is running) to gat any trapped air out of the head and into the reservoir.

[PichaDis11]

Originally Posted by Efthreeoh

It goes to the highest level of the cooling system, which is the top of the reservoir. When you open the reservoir, you top off the coolant to replace the volume of air that was trapped. That's why you fill the cooling system with the bleed screw open because that is where the air escapes from the head as you fill the cooling system. Then you close the cooling system completely (so it builds pressure when the pump is running) to gat any trapped air out of the head and into the reservoir.

Ahh thanks for that explanation.