korpse88

Car started overheating bout 10 days later with the Engine Temp shut down car now warning. I live in California and it's been in the mid 90's.

Anyone think the distilled water is the culprate?

Also, oddly enough 10 days ago, the SES and Gas Cap warning came on at the same time, I figured it was the gas cap problem and it would go away. It hasnt yet and is throwing the P0442 code, which I definitely think is the gas cap. But as far as the overheating, is that the distilled water problem?

Don't make fun of me, but I was considering turkey bastering the water from the reservoir and putting in legit coolant? Dumb idea?

e60rider

I dont think so, since i know some people that run a blend of 70 percent water to coolant ratio. If anything, it will change the freezing point of the coolant but shouldn't affect it performance much to cause a warning light. How much water did you add?

zach1328

Adding distilled water isn't bad. It's not a good idea to run only distilled water for too long especially in that hot climate.
Theres no need to drain it though. How much did you add in?
As long as the mix is pretty close to 50/50 you'll be good. Just buy some Coolant (not the premixed kind) and add roughly the same amount of coolant as distilled water you added.

korpse88

Well the actual reservoir was not bone dry, probably a 1/2 - 1 inch full, definitely at the min though. So filled it up to full with distilled water. So basically a whole reservoir worth.

The radiator fan also seems to be loud as all heck too now. Constantly sounding loud and running like its working hard, from right when i start the car.

Since the reservoir is still full, can i just turkey baste some out and add some actual coolant?

DavidF

If the engine is running hot, it is not because of the distilled water. Even on pure water, the engine should not overheat. But, pure water is not good as the coolant provides additional water pump lubrication and (aluminum) corrosion protection. Find the leak and repair it. Inspect the thermostat and insure it is working properly. Drain the system as much as possible and add back a 1.25:1 coolant/water ratio. Heavier on the coolant to compensate for your current water heavy mix. Normally, you would use a 1:1 mix.

E60I

Bleed the system and see if that will fix your problem. If your car has an electric water pump, listen to see if it's working. Do you have a code reader to see what's registered in the system?

Better yet, why don't you just buy one gallon of BMW coolant and do a complete flush, refill and bleeding? You can re-use the new coolant as long as you don't contaminate it; just in case if you have to replace the thermostat or water pump afterward.

korpse88

I ran the accelerator/10 second test and it triggered the waterpump to work, I also ran it with the cap off to visually see that it was working.

I had an OBDII reader but it is not showing anything other than P0442 which is the Gas Cap problem.

About 6 months ago the water pump replaced, the coolant doesn't appear to be leaking unless very minimally. Do you think the thermostat may be stuck? Is there any way I can inspect the Thermostat without jacking the car up?

The Distilled water has only been running for about 10 days. I've read that water's boiling point is 220 while coolant is 387'F, it's really hot in California so I thought maybe it was getting too hot.

Perhaps it is not the water that is causing the overheating. I think it's the Thermostat being stuck, is it possible to inspect it without putting the car on jack stands or do I need to take the car in. The water pump was replaced 6 months ago but I don't believe the thermostat was. Water pump is working to my knowledge after running tests.

E60I

If the water sensor (can't think of the real name right now) is working, I'd change the thermostat. I hate to say this, but you should have changed the thermostat when you changed the water pump; after all, they work like a team and get tired and worn down just about the same time.


Sorry, I don't think you can check the thermostat without removing it. It's an easy DIY.

korpse88

I have a mobile mechanic coming to check out my car in a couple hours, $100 diagnostic fee but will go towards repair cost if I use him. Offers free tow to and from his shop. Seems legit, I will keep you guys posted on what happens later today.

korpse88

Was showing code P1554 and after looking at the car, the mechanic said the water pump and thermostat need to be replaced. Quoted me $1700.

Looks like he's out to make some serious cash on me. I'm not that dumb