Today I noticed the engine temp rising a bit. [Solved]
 

A couple of weeks ago I started getting the coolant level low warning, It would come up randomly and just for a couple of seconds.
I still need to figure out why, and I'm going to check the sensor connection as suggested.
(The coolant level is fine)

But I hadn't have any problem with the engine temperature before.
The needle was either all the way to the left when cold, and at 12 o'clock when at running temp, and never went higher even with the summer temps here in Las Vegas, but today I noticed that when I was stopped during a red light, the temperature went up, not all the way, but a little before the "red zone"

Then when I started driving went back down again, The fan in front of the radiator is fairly new, and I'm pretty sure that I've heard that is working a couple of times this week when I got home and turned off the engine.
I didn't heard it running today, so I guess that is a possibility, but assuming the fan is right, what else could be causing that change in temperature?

Thanks !!

Today I noticed the engine temp rising a bit.
 

The temperature indicator on the dash is not a gauge it's a 3-step idiot light.

It's designed to snap to 12:00 for about a 30°C range of temperature. It will erroneously indicate proper temp over a very wide range of not good temp.

If it ever goes past noon it's already overheating. You said the coolant was low ? Resolve why. (Usually a leak in a hose fitting or the overflow reservoir).

Use the hidden menu to monitor actual ect (engine core temp) or coolant temp I can't remember which is accessible from that menu but you'll see how relatively worthless the non-gauge is on the dash.

- What is your mileage? Mileage is always important i any new post seeking help.

- I did the partial cooling overhaul at 113K. I am now at 130K and still rock solid.

- Here is the DIY:

https://xoutpost.com/bmw-sav-forums/...16k-miles.html

No, the level of the coolant level is fine, the expansion tank, the water pump that thermostat and the hoses are new.
everything was replaced a couple of months ago, and no leaks or coolant level dropping.

I have to drive to Pahrump tomorrow I will use the hidden menu to monitor the temperature, it's about 100 miles round trip.
But is highway, so I don't know if the temperature will rise.

Quick update, I just figured out that the fan clutch is FUBAR, I noticed that was almost freewheeling with the engine off and just pushing it with my hand, then I started the engine and use some paper and it stop.

So I ordered a replacement, that should be here Sunday.

2 questions:

1- I guess this could be the culprit of my problem right?

2- it it risky to drive 100 miles with the fan clutch not working? (freeway)

The fan's job is to push air of the car isn't moving. It doesn't do much at highway speed if anything.

Monitor temp and you will be fine also the electric fan should kick in if the tempo gets hot enough.

The clutch is meant to be pretty free I'm able to stop my fan with cardboard when the engine is running.

When my thermostat was broken open I blocked my fan so I could have heat inside. I only used a piece of foam.

Did you say you replaced the thermostat? Stuck closed tstat will give you over heat.

Thank you, I'll be checking the temperature.

Yes I replaced the thermostat, a couple of months ago, but I guess failure is possible too.

As for the clutch, I hope that's the culprit, I will replace it, and report Monday if the problem was fixed.

The only way to potentially avoid overheating is to overhaul the cooling system every 125k/mi or so. But doesn't prevent new part failure, sadly. Hope you figure it out before something bad happens. Are you sure you dont have a bubble in the system?

If it's running cool it's usually due to a thermostat that's stuck open. That's better than stuck closed. It just screws your fuel mileage.

So I replaced the clutch, but as soon as I started the replacement, I figured that the clutch was not the problem.
When I removed the plastic covers, i noticed leak stains on the expansion tank, so the tank obviously failed even though is basically new (3 months).
I'm ordering a new tank, but I have a question, is there a way to check the thermostat?
Is new too, but I don't want to drain the system to replace the tank, and then figure I need a new thermostat too.

Another question, when replacing the tank, should I order the transmission thermostat too?
Its also 3 months old.

Thanks !!

- Probably Behr Chinese reservoir that fails in 3 months.

- Best is to go to ebay, at this moment, there is a seller "cenauto" selling OEM reservoir for $55 (instead of the usual $95 price).

https://www.ebay.com/itm/Genuine-BMW.../122630659270?

I just bought one for my 2004 X3 for $55, and it is genuine BMW reservoir.
There are only a few left at that price.

When I bought my reservoir it came with the thermostat. On an aged car the tstat will self-destruct upon disassembly

Aghhh that's exactly what I think I have is a Hella Behr, I guess is the chinese one because it failed in less than 3 months...

Until you see the crack, and see the coolant leaking out of it, I would not assume the tank has failed yet.

If there is an overpressure condition, the cap on the expansion tank will vent coolant, allowing it to flow onto the tank, etc.

If your engine overheats, you might warp the head or damage the head gasket. That would allow combustion gases to enter the coolant, raising pressure beyond the 2-bar cap release setting, allowing coolant to exit through the underside of the cap.

And I know all this because I went through it all on my 2001 3.0i earlier this summer. In my case it was a slightly warped head.

Here's a post on how you can pressure test your cooling system, if you can rig this thing up:
https://xoutpost.com/bmw-sav-forums/...ystem-e53.html

For me, doing that test ruled out any cooling system leaks, so I moved onto the next test, which was a Lisle combustion gas detector, giving me the bad news.

If all of this testing is beyond your limit of tools availability, you could try this as a test:
Clean and hose everything off around the expansion tank. Roll up a paper towel and wrap it around, under the expansion tank cap. That is where the pressure-released coolant comes out - between those ribs on the bottom of the cap. Then run the engine / drive around until it leaks. If you see leaks below, and on the expansion tank, but the paper towel is dry, then it is not the expansion tank releasing. If the paper towel has coolant on it, it could be what I'm suggesting above, or it could be a failing cap (o-rings, etc.) that is leaking even though the coolant is not over-pressurized.

Thank you, I don't see any liquid stains close to the cap, but I guess is possible that the tank is not leaking, I saw your post on how to test the system pressure (genius), but I don't have the bleader or a spare cap.

But I will definitely get a combustion gas detector kit to make sure is not the head gasket and ruin the engine while focusing on the cooling system.

Drive until hot (to pressurize) and if leaking from the seam you'll see a drip forming. Alternatively, stuff paper towel where you see the leak stain and after a drive or two the evidence should be clear.


Sent from my iPhone using Tapatalk Pro

I edited my previous post, adding the last paragraph, which maybe you missed. It would be a way to do a simple test before buying that Lisle tester.

The Lisle tester is about $40 and your local PepBoys, etc. might have them. I paid more for mine there, vs. waiting a couple of days from Amazon (which was cheaper).

In my post on the pressure tester, there is a link to my warped head problem and solution.

If you've got a warped head or head gasket, I doubt you're going to hurt it too much by driving it until you eventually fix it. But you can at least save yourself from diagnosing and replacing a ton of other parts you don't actually need to replace. In fact, if you do have that problem, you may have had it for a while and not known it.

BTW, I don't know if this is what happened to you, but I tell you, from going through this experience on my car, I now look at used car ads for the X5's much differently. MANY of them are offered as needing a new radiator, coolant leak, etc., passing off a possibly major issue as a minor one. That's not what happened to me - I've owned for 4 years now. And actually, I think that most of my warped head was probably caused when the PO had a major problem at 158k a year or so before I bought it ... and then a recent problem put it over the edge.

So maybe everyone should buy that Lisle kit and take it with them whenever they go used car shopping.

Too late..
I already ordered a Combustion Leak Detector kit, Funny because I got the reservoir and the liquid separate and end up paying 27 instead of almost 40.
I really hope I find that was an unnecessary buy, but I'm not looking forward for a head gasket project, and better be safe than sorry
Anyway, I think is worth having it around.

This whole problem started with getting random warnings for a second or two about low coolant level, but everytime I open the cap, the little rod pups up.
So I guess there's something funny going on with the expansion tank anyway.

Reservoir full and low coolant warning indicates a problem with the sensor


Sent from my iPhone using Tapatalk Pro

Agreed. That's another problem you should get figured out. Probably pretty easy. There is a little electrical connector at the bottom of the tank (bottom, rear, driver's side) with two thin wires going to it. It could be that leaked coolant residue is interfering with the connection there at the plug/socket. First thing to do is to unplug, clean, etc.

And of course, if the sensor is saying one thing and the floating rod is saying another, believe the floating rod.

If the problem is not at the connection, that magnetic float sensor has been known to be flaky (or even non-existent) for some non-BMW brands.

BTW, if you do end up having an issue with your sensor (i.e., not the connector, your tank is good, etc.), this thread has a ton of info on it. Pics of it cut open, etc. so you can see what that float looks like, the connector location, etc. After all the mysteries about its workings are discussed, the answer is given (I think) in post #16.
https://xoutpost.com/bmw-sav-forums/...l-message.html

But the sensor problem is separate from the leaking coolant problem - solve them both.

Depends on where you got it and where it was manufactured. If it's URO, it's usually junk and that's why it didn't last, Buy the parts from manufacturers that manufactured the original part. Doesn't have to have a Roundel on it as long as it was manufactured by the OEM. The crap made in China doesn't last. It's cheap for a reason.

Thank you all!

It was both, the level sensor (that was old)
And the thermostat that was new and failed in less than 3 months
I replaced them, and all seems back to normal !

Now just need to fix the programming of the idiot temp dial.


Sent from my iPhone using Tapatalk Pro

How do I do that?
Seems to be working fine.

"fine" as in normal is basically a 3 position dummy dial. its either cold normal or hot. Hes referring to re-programming it so the hot and cold portions are more accurate. I want to do this also. https://xoutpost.com/1121333-post23.html

That's exactly the problem. It always seems to be working fine. There is about a 40° range sheet it points to noon


Sent from my iPhone using Tapatalk Pro

Oh, thank you both !!!


I'll Read that and try to do the programing !
That needs to be done for sure !

Glad you got things fixed. Thanks for following up. Tough when there is more than one failure to confuse the issue. :thumbup:

What was the brand of the new thermostat that failed? Could you tell exactly how it failed?

A couple of months ago, I posted that after a tune up, my mileage was worst, someone suggested me to unlock the hidden menu and check the temperature, so I did.
And the temperature was jumping, not too bad but between 90 and 104.
Anyway, I totally forgot about that.
Then:
It started with random "Low coolant level" warnings, that would come and go. (That was obviously the sensor)

But pretty soon after that I saw the temperature gauge go up (at around 1 o'clock) and then back down ant 12.

That's when i started this thread, and while I was trying to decide what to look at, I remember that someone had mentioned on my other thread, that, that variation was not right on the thermostat.
I'm not sure what the brand was, but had good Amazon reviews, the only noticeable difference was that the connector had a different orientation.

So I decided to get a new one from ebay (following a link that someone posted on this thread), and voila !!