[E31BMW]

My friend’s 07 335i is overheating. The oil temp is fine, but after a short drive, the water temp symbol lights up and says the car is too hot to operate, followed by limp mode if he continues to drive. After checking the fuses and verifying they are fine, I told him the water pump, which was replaced about 6 months ago is faulty. The BT tool says the issue is the electric cooling pump; what do you guys think?

[bo1o02]

replace water pump and gasket

[mike3000fl]

easy way to tell.

wait for car to cool down. cold enough to remove the cap from the coolant reservoir/tank.

run the water pump vent procedure (find it in the DIY for doing a coolant change). look in reservoir for coolant flow. it should piss fluid from a small hose into the tank. if it flows the pump is working.

pretty easy procecure, turn on ignition without starting car, hold down gas pedal for 10 seconds (might be 12seconds).

[PINeely]

Sounds like water pump or T-stat.

[mike3000fl]

Originally Posted by PINeely

Sounds like water pump or T-stat.

thermostat fails open. won't cause overheat, if anything it will run cool and cause the car to be less efficient. take longer to warmup and all that, in cold climates it may never warm up to full op temp.

[PINeely]

Originally Posted by mike3000fl

thermostat fails open. won't cause overheat, if anything it will run cool and cause the car to be less efficient. take longer to warmup and all that, in cold climates it may never warm up to full op temp.

Well that's a handy feature, it's warm enough here that when mine goes I won't have to replace it immediately.

[blingman]

When car is cool, open up the cap on the coolant tank and check the coolant level, if it is normal I would suggest, bleeding air out the system just in case there may be air in there causing car to overheat. At the same time, you will know if your pump is working or not.

Procedure to bleed air: key in with FOOT OFF the BRAKE, press the start buttom(accessories lights are on), put temp to max hot and fan speed to low. Press on gas pedel down and hold for 15-20 seconds or little longer and you should hear the water pump turn on(water pump is located on the passenger side up from right under the radiator, next to the a/c compressor area). As some people suggest, you may want to get a charger on the battery since this process last 15 minutes or so and can drain your battery. I've done the bleeding procedure on my car 5 times so far without charging it and never had a problem starting it up and battery has been fine since. After the water pump stops, I removed the key and open up the coolant tank cap again to check the coolant level, if it went slightly down, that meant there was air in the system which you should hear the venting when you open the cap. Top off to normal range and I usually do the bleeding procedure twice to ensure all air is out.

[blingman]

Originally Posted by mike3000fl

easy way to tell.

wait for car to cool down. cold enough to remove the cap from the coolant reservoir/tank.

run the water pump vent procedure (find it in the DIY for doing a coolant change). look in reservoir for coolant flow. it should piss fluid from a small hose into the tank. if it flows the pump is working.

pretty easy procecure, turn on ignition without starting car, hold down gas pedal for 10 seconds (might be 12seconds).

I thought I was the 3rd to reply, but after that long post I typed and hit submitted I saw your post and others LOL.

[E31BMW]

Thanks so much for your help.

[mike3000fl]

Originally Posted by blingman

I thought I was the 3rd to reply, but after that long post I typed and hit submitted I saw your post and others LOL.

we think alike, lol

you have the full procedure in there, which is awesome, i could not remember all the details.

[bbstoke]

Took mine for it's M.O.T today and as usual it passsed
The tester put a device on the accelarator that took it to 3000 revs and kept it there whilst doing the emmisions test.. Sounded like he had it on for about 10 minutes.
As he did the other checks the car was running all the time.
When he finished I got back in the car and a yellow warning light was on (tempreture) then it went to red.
After driving it for 10 minutes it went off.
Shouldn't a fan kicked in?
Anyway all seems fine now ,checked the water level when it cooled and it seemed fine.
With the light going off does this mean the pump is OK and it's more the fan?

[Blackhawk36]

Originally Posted by bo1o02

replace water pump and gasket

The water pump doesn't have a gasket.

[pratan158]

Water pump and thermostat. I just had that problem 2 months ago

[bbstoke]

Originally Posted by pratan158

Water pump and thermostat. I just had that problem 2 months ago

Is that reply to me?
Was it an expensive job?

[pratan158]

Originally Posted by bbstoke

Is that reply to me?
Was it an expensive job?

no..to the topic..i did mine at an indy shop for $1000

[alpinewhite335]

i had the same problem last month . l paid $1030 with everything .

[bbstoke]

And I thought things were expensive on this side of the pond!
Went to a specialist yesterday and was quoted £280. Quite pleased with that

[Blackhawk36]

Originally Posted by bbstoke

And I thought things were expensive on this side of the pond!
Went to a specialist yesterday and was quoted £280. Quite pleased with that

What motor is in your e90. The 335i has a 450 watt motor in the water pump and it is considerable more expensive than the 250 watt in the 328i.

[bbstoke]

I'm not sure.. It's a 318i (Don't laugh) :-)
So I imagine it's the 250 watt