Intermittent over heating

Z

z4man2020

Member
Hello Everyone.

My 2006 2.5 E85 Face Lift has developed an overheating problem.

The temperature shoots up all of a sudden. I have to switch it off before the red light flashes. If i switch it back on after a couple of minutes the gauge goes back to normal. Type of driving doesn't seem to effect it.

The fan also doesn't spin when its near overheating (one would think it would be working overtime?)

:driving:
 
Chris_D said:
new thermostat time.
and you may as well replace the waterpump.
Click to expand...

Okay mate.

From your experience would you say that's it?

I had a thermostat go on my Z3 once and it was constantly reading cold! :rofl:
 
z4man2020 said:
Chris_D said:
new thermostat time.
and you may as well replace the waterpump.
Click to expand...

Okay mate.

From your experience would you say that's it?

I had a thermostat go on my Z3 once and it was constantly reading cold! :rofl:
Click to expand...

tbh it could be anything to do with your cooling system. but you need to start somewhere in order to diagnose.
i assume you have already checked the obvious like coolant level, leaks etc?
temp 'shooting up' would indicate to me at least that you have a serious overheating issue somewhere at least and you shouldnt really be driving your car without addressing this asap.
clarify in seconds/minutes 'temp shooting up' is. it should be a couple of minutes in an M54B25 if your coolant tank has ruptured or water pump has failed and not instantaneous as in the N52.

Could also be a faulty temp sensor.
Get a code reader on it to see if there's any codes throwing.
 
As your car is a facelift 2.5 it will have the N52 engine with the electric water pump.

Unlike mechanical pumps that wear and gradually get less efficient the electric ones just stop! So the coolant doesn't circulate.

When the pump died in my 1st E86 the temperature went from normal to the end of the gauge within about a mile, which sounds like what you are experiencing but if you can get access to a code reader that will confirm the problem.

If it is the water pump whatever you do don't but a new one from BMW as they charge over £500 for them! You can get the same Pierburg pump other places for about half that.
 
....or even take a punt at a £80 ebay special?

https://www.ebay.co.uk/itm/372874216232
 
Right lads

I've plugged my home reader in and no code has been generated (i can appreciate i may need a bmw one)

Took the car out this morning.

It shoots up a bit as seen on the photo.

Then it waivers and gradually goes to red.

I've got a video but I have no idea how to attach it :rofl:
 

Attachments

  • IMG_20201011_093641.jpg
    IMG_20201011_093641.jpg
    94.3 KB · Views: 1,501
From inside the cab i can hear a motor/fan spinning but upon inspection underneath the bonnet the cooling front fan doesn't seem to be working :tumbleweed:
 
Mr Tidy said:
As your car is a facelift 2.5 it will have the N52 engine with the electric water pump.

Unlike mechanical pumps that wear and gradually get less efficient the electric ones just stop! So the coolant doesn't circulate.

When the pump died in my 1st E86 the temperature went from normal to the end of the gauge within about a mile, which sounds like what you are experiencing but if you can get access to a code reader that will confirm the problem.

If it is the water pump whatever you do don't but a new one from BMW as they charge over £500 for them! You can get the same Pierburg pump other places for about half that.
Click to expand...

What do you think of the symptoms mate?
 
Chris_D said:
z4man2020 said:
Chris_D said:
new thermostat time.
and you may as well replace the waterpump.
Click to expand...

Okay mate.

From your experience would you say that's it?

I had a thermostat go on my Z3 once and it was constantly reading cold! :rofl:
Click to expand...

tbh it could be anything to do with your cooling system. but you need to start somewhere in order to diagnose.
i assume you have already checked the obvious like coolant level, leaks etc?
temp 'shooting up' would indicate to me at least that you have a serious overheating issue somewhere at least and you shouldnt really be driving your car without addressing this asap.
clarify in seconds/minutes 'temp shooting up' is. it should be a couple of minutes in an M54B25 if your coolant tank has ruptured or water pump has failed and not instantaneous as in the N52.

Could also be a faulty temp sensor.
Get a code reader on it to see if there's any codes throwing.
Click to expand...

Cheers bud.

Added more symptoms :driving:
 
Stop driving it as you risk damage to the head with high heat cycles.
Swap in a new stat and waterpump asap and report back.
 
z4man2020 said:
What do you think of the symptoms mate?
Click to expand...

I'd be very surprised if it wasn't a dead water pump if you've eliminated the obvious like leaks and/or a split expansion tank. It might be worth seeing if the radiator feels hot when the temperature gauge is getting up the range - if not that suggests the coolant isn't circulating.

You don't want the engine getting that hot too often, although if it gets too hot it will go into limp mode - as I discovered. :roll:

Personally I'd try to get a BMW code reader on it and if it is the pump I'd replace it with an OE Pierburg pump - just not bought from BMW!

Hope you get it sorted.
 
Now looks like I'm too late to the party, but, having just done the same simple diagnosis on my wife's 2.5i, albeit with the M54 engine, you can try popping the expansion tank cap off and looking in with the engine running. I was seeing significant movement of water in there, with a 'return' running in at the top. If the pump was not working at all you could expect to see no movement.
 
Weird outcome....

After further investigation remains of a bird were found. Wiring torn.

Wiring replaced, works perfectly now.

Think the girlfriend must of hit something :rofl:
 
Water pump expired yesterday on my 2007 3.0si and had to be towed to the garage.

Any recommendations for where to buy the Pierburg pump?

And any recommendations for where to buy a thermostat as I might as well get that reaplaced at the same time?

Finally, is there anything else I should look to get done at the same time?

TIA
 
Euro Car Parts sell the Pierburg pumps so look for one of their offers, but I think there are others like carparts 4 less. Just avoid BMW as they charge over £500 for the pump. :o

I can't remember who made the OE thermostats, but hopefully someone will know. I don't think there is anything else to be done if you are having the pump and stat replaced.
 
You must log in or register to reply here.
Back
Top Bottom