Overheating when stopped! Please help!

[325ic]

PLEASE HELP!

My car is running hot when I'm stopped for a little while or at a stoplight. My guage will jump up to the scarry side and then go back down as soon as I start moving. It started this out of the blue.

Background: a few months ago replaced:New radiator, new thermostat, new upgraded water pump, new overflow tank, new sensor, new heater control valve. (Had a bad water pump and a stuck thermostat.)
I'm going to check the levels and fuses tonight after work. I was told by the import mechanic that replaced all this that the fan clutch was going bad and could use replacing but was not a must.

What is this about the aux. fan and another fan with the AC? I'm not understanding this.

[bimmerboy328i]

Any leaks? Could be your valve gasket.

Sorry, I had too, really bored.

[silverstar]

BLEED THE SYSTEM again

[hellrot325]

Don't use the stupid fonts and don't do that to a BMW!

Ok, to your issue...there are two fans, one belt driven and one elctric fan.

The belt driven....that has the clutch that the mech said is bad, should be drawing air all the time and will cool the motor even when not moving. If its bad, replace it. The viscous clutch is a common failure item in higher mileage E36's. mnay of us replace it with the "fan delete" mod.

The auxiliary fan is electric, and comes on when:

1) engine temps hit a certain level....88C IIRC
2) or when the AC is on.

If your belt fan is bad this should keep the engine from overheating when not in motion. With a fan delete mod you replace the aux fan switch to come on at a lower temp, and add RedLine Water Wetter to the coolant for more efficient heat removal. I have done the fan delet mod and never had an overheating issue.

Either do the fan delete mod...amke sure the aux fan is ok, or replace your belt fan. Take care of these issues or you will overheat, and can very easily blow your HG which will cost you $1500-$2000 to replace.

[Michael H]

I have them same exact car. Check the thermostat and water pump.

[dmurray14]

Don't use the stupid fonts and don't do that to a BMW!

Ok, to your issue...there are two fans, one belt driven and one electric fan.

The belt driven....that has the clutch that the mech said is bad, should be drawing air all the time and will cool the motor even when not moving. This fans viscous clutch is a common failure item in higher mileage E36's. Many of us replace it with the "fan delete" mod.

The auxiliary fan is electric, and comes on when:

1) engine temps hit a certain level....88C IIRC
2) or when the AC is on.

If your belt fan is bad this should keep the engine from overheating when not in motion. With a fan delete mod you replace the aux fan switch to come on at a lower temp, and add RedLine Water Wetter to the coolant for more efficient heat removal. I have done the fan delete mod and never had an overheating issue. Removal of the belt driven fan also improves throttle response...

Either do the fan delete mod...make sure the aux fan is ok, or replace your belt fan. Take care of these issues or you will overheat, and can very easily blow your HG which will cost you $1500-$2000 to repair.


Post whore! :stickoutt

[atlantisvip]

BLEED THE SYSTEM again


I agree.. Also, your thermostat might be stuck again and not opening so your radiator is depending on the air it gets when your car is "in motion" for cooling..

[amancuso]

I would listen to Hellrot on this one..

[silverstar]

IF IT WAS YOUR FAN CLUTCH.
i just did the fan delete mod so i have the fan clutch for sale. let me know whats gona happen.

GOOD LUCK.

[inlinesixm3]

I have them same exact car. Check the thermostat and water pump.
went through the same thing and it was the water pump i had the plastic propel on the old 325is changed it to the new metal ones and new thermostat problem solved

[beatniks325]

to add what hellrot said, the aux fan is the one you can see through the grills and the clutch fan is the one attached to the water pump in the engine bay.

if the import mechanic thought the fan clutch might need replacing, then I'm guessing something is probably wrong with your aux fan (or fan temp switch) too, as like hellrot said, the aux fan should be able to prevent overheats on it's own (unless you are stuck in traffic for hours and hours or something)

start the car
turn on the air conditioning
go to the front of the car and check to see if the aux fan is running.
this will test the lo-speed of the aux fan switch

to test the hi-speed you need to get your car engine hot enough to throw the switch, which must be done with care so you don't overheat again.

one last thing, check to see if you get hot air out of the vents (with heat oh duh) while the engine idles and when the engine is under load.

[hellrot325]

Post whore! :stickoutt What the heck does that mean? And listen to beatniks, because he is widely recognized as "Mr. Aux Fan Man" :D Seriously.

[hellrot325]

Post whore! :stickoutt I'm guessing its because of my double post I see...not sure how that happened. Deleted one so as not to make you a "Post John" ;)

[328 is man]

my symptoms are the same. dealer says its the aux. fan. 277 for the parts from bimmerparts.com + 3-4 hours of labor. dealer wanted 600 just 4 the parts

[silverstar]

Is the car leaking antifreeze? mine did that when the water pump gave up but it started leaking right away....

[325ic]

Any leaks? Could be your valve gasket.

You mean head gasket? :rolleyes

[325ic]

I have them same exact car. Check the thermostat and water pump.



Background: a few months ago replaced:New radiator, new thermostat, new upgraded water pump, new overflow tank, new sensor, new heater control valve. (Had a bad water pump and a stuck thermostat.)..
:(

[325ic]

Thank all of you who read my post and responded. I'm going to check on the aux fan right now. I turn the car and ac on and look in the grilles right? BRB

As for the fan delete, anyone do this in FL or a hot as Hades location without any problems?

Thank you all again.

[beatniks325]

Thank all of you who read my post and responded. I'm going to check on the aux fan right now. I turn the car and ac on and look in the grilles right? BRB



yup

[325ic]

Ok, checked the coolant level in the catch can (when I opened it went PSHHHT...) :D , checked the fuses none blown. I checked, and yes I see a fan turning in the grill area. I also looked at the belt driven fan and it was turning also.

I then let the car sit for about 10 mins with the a/c on with my foot on the gas at about 2k. The car did not spike in temperature like it has all this week. I won't know for sure until I'm driving home tonight. Now I'm really stumped. I don't think I could get the engine hot enough to see if the thermostat was opening. I will have to check it when I'm not stuck at work 1/4 of a mile away from my car. :(

Could I have had an air pocket that released when I opened the catch can?

[beatniks325]

maybe i should have mentioned that you shouldn't have the ac on when you want to test the high-speed of the aux fan switch. if you have the ac on then the aux fan will be on low-speed all the time, see what i mean?

yes it is possible that the rush of air you heard let out some air in the cooling system. it is also possible that there is more left in it too.

what are you getting for hot air out of the vents like i asked you to check?

[dmurray14]

I'm guessing its because of my double post I see...not sure how that happened. Deleted one so as not to make you a "Post John" ;)


I'm just messin' with ya...but yeah, I was talking about the double post. :stickoutt

[325ic]

Ok, I did check the heater and it does blow hot air. Since I opened the catch can and had the air burp. I have driven it in bumper to bumper trafic and then sat in a parking lot for 30 mins with the engine running and no overheating whatsoever. I recenly had my car in the shop to have the H&R's and Bilstiens installed. I wonder if they did a dis(service) for me and checked the cooling system creating air pockets or something. Thanks to everyone's tips. I'm still skeerd lol so I'll be double checking everything as soon as I have some time off.

[beatniks325]

if they checked the expansion tank by taking the top off when the car engine was still warm, then yea it is possible they introduced some air into the system.

[328 is man]

ok, i was told my problem was my aux. fan and i have the same problems as you but i checked the other day and my aux. fan was on and the car was still overheating any ideas what else it could be?

[325ic]

don't know the background of ur situation but... My car was acting up when the water pump was bad (the shaft was spinning in the impellar), and ultimately the thermostat stuck shut causing the heater control valve to burst under pressure.