Cooling Fan Malfunction?
 

I've noticed recently that my cooling fans do not come on by themselves after I shut the car off, following a spirited drive in relatively high heat. Last year I did notice that they would come on periodically in this circumstance. I do tend to allow for a decent cool down period before I shut it off, but this part is kind of strange:

*The only way I can get the fans to come on is to turn the key to accessories after turning the ignition off. If I turn the key to off the fans will go off almost right away. Turn key back to access. the fans will come back on.

Anyone know what could be the problem? Or, is this something I should even worry about? As I said, I allow for ample cooling time before I park anyway.

(coolant level is at full btw)

My 8 also does that. I keep telling myself to purchase the fan mod.:banghead:

Hmmmmm...a reverse fan mod..........you planning on doing a DYI? Sorry..........ummmm.........you could check the relays but that doesn't seem likely.
You sure the fans aren't already on when you shut the car off in this instance? They actually come on after the car is shut off?
My best guess would be the computer isn't telling it to keep them on after the car is off........when it's above the threshold. When you do turn it back to ACC, do they go off after a few seconds or a few minutes like the should? This is really stupid but how is your battery voltage...................could it be low?

i once had my high speed fan relay blown ...good thing i had defi water temp to indicate the abnormal rise in temp

The only way I can get the fan to come on is to turn the key to ACC after turning the car off. If I leave it on ACC the fans will stay on for a little while. When I turn the ACC OFF the fans turn off almost immediately.

Its pretty clear when the fans are on and when they are off, b/c they are pretty loud.

Any other ideas aside from a blown relay? That sounds very plausible. When I've got the car at the dealer next week for new headlights (hazing inside) and clutch cut switch TSB, I'll have them check that out.

No one else with this problem?

It's the right time of year and they are on sale @ Mazsport.net

Theres no way to know if theres a small problem unless you got real temp gauges.

Im pretty sure if it was a big problem you would get a coolant light or a CEL if the engine was actually overheating.

This happens to me as well. I just drove from Chicago to Cincinnasty and when I pulled into the house and turned the car off nothing - no fans (4.5 hours of 80+ deg outside). I turned it to ACC and the fan ran on low for a few minutes before kicking to high for another few min and then back to low. Total of 10+ min before they shut off.

The only reason I turned it on to the ACC was because this had happened once before but after the engine died while driving. I went to try to turn the car over and as soon as I turned it to ACC I had fans blowing on full. The engine was replaced days later (June 07) and I just had the most recent flash done a couple of months ago.

Help? I know they should be on but I shouldn't have to turn the car off and then to ACC/On to get them to go.

I think Im in the same boat as you guys.

I do have a real temp gauge, the sensor is located between the water jacket and engine.

After the MSP16 flash, the water temp is ALMOST ALWAYS above 100 Celsius. Its pretty hard to get it under 100. and of course, after car shut down, the temp is reading like 105, which should be hotter at the temp sensor behind thermostat. but like Rhythmtic, fan does not turn on after shut down, and I have to turn the key back to "on" not starting the engine to get the fan to turn on.

According to "various" reports, Koyo is part of the "heat soak" problem, Im going to replace it soon.

hmm, makes me want to reflash my ECU to RB's flash. (thats 150 bux :()

what you describe is normal..

if you're out driving and coolant temps are hot, the fan will remain on when you turn off the vehicle. HOWEVER if you put the key back in, go to ACC then off, it will shut off the fans.

The reverse can also work. If you drive the vehicle, and it's cool enough to not need the fan, you can put the key in, turn to ACC then off, and the car can decide to turn on the fan for a bit if it thinks the coolant temp is too hot for "off" position or whatever it thinks is going on.

I do that sometimes when I park it in my garage and the fan isn't on. Usually it will only start up for a few seconds before going off, but sometimes it can go on for a little while longer.

I noticed a while back that my fans weren't kicking on when I thought they should, after long drives and temps warmed up. I didn't think much about it, and then I blew an apex seal.

I had no indication that it was overheating (no aftermarket guages), never lost coolant, temp guage gave no indication. I started getting power loss during long cruises when it was hot outside.

Engine + both cooling fans replaced. If you have a hunch that something's not right, better have it checked out.

It is weird.

Constant 100-107~ Celsius water temp does not sound good to me. Im not even pushing my car hard. Not to mention the temperature Im reading is after the thermostat, so the Actual Temp should be couple Celsius higher.

Im not driving my car until another Radiator comes in. Thinking about going with AP, but hmm money is kinda tight lately :(

Sorry I don't buy that. The car doesn't think, it bases it's actions off of certain parameters such as coolant temp, etc. It doesn't not turn the fans on after a 4.5 hour drive but then when I put the key to ACC decide, "you know, this guy's right" and go though a 10+ minute single, double, single fan dance.

The time I mentioned before where the engine died and the fans didn't turn on, as soon as the engine died I turned the key to off and then tried to turn it the engine over. When the key hit ACC the engine temp needle pegged H and the fans came on full power. Yet it didn't turn them on after it stalled out (and the needle was in the middle).

Clearly something is wrong but what can it be? Relays, Temp sensor, etc?

Good thing for that 8yr warranty now! :) I do notice that I can actually hear the rotor spinning after my trip. Ugh. So did your fans never come on? Only when you turned the key to ACC? Or did they intermittently come on after shut down.

Yeah, you're right. There is no possibility for the car to reevaluate what the min temp is at initial ACC power up. :banghead:

I happen to monitor coolant temp, my radiator fans turn on when they should and shut off when they should. If you don't believe me, you should try installing gauges instead of outright dismissing something. I believe this to be normal operation because it happens to be normal.

Mine just weren't coming on when you would normally notice them, after the car is shut off. Never tested whether they would come on with ACC. But I thought, well it's spring and temps haven't really warmed up yet. Then when we get an occasional warm day, I sorta dismissed it again, mainly because 1) my cat failed and I assumed that was the reason for my power loss, 2) coolant level was consistent, 3) temp guage gave no idication, 4) temp warning light never came on... This is what concerns me. No warning.

In my case, the fans weren't spinning freely, putting too much load on the system and blowing the fuse. Whether it was the bearings or the dreaded rubber grommet from the air box, I don't know... but I am very scared to check my air filter now.

heh. The built in gauges in the car for coolant is worthless. It will basically alert you to the fact that you might need a new engine.

LOL Maybe true but the flashing CEL, limp mode, and tractor noise is a DEAD giveaway. :)

Same situation today. 92 degrees and shut the car down after a 30+ mile drive. Nothing - no fan. Turn it off, wait - nothing. Turn the key back to ACC and one fan comes on. Turn off pull the key out and the fan shuts off. Put the key back in to ACC and the one fan comes on and remains on for 10min. Big fan never kicked on.

What could be wrong? Why aren't they coming online by themselves and staying on if the car is shut off?

Is there a way to test the fuses/relays? I watched the Mazsport cooling fan video which shows that there product replaces fuse/relay "Cooling Fan 1" & "Cooling Fan 2". However at the top of the box is another fuse/relay labeled "Cooling Fan 3". What does that control?

Help please!

30 mile drive doesn't mean anything. At cruising speeds your coolant temps might be at 180F for all you know. I find my coolant temps rise the most while at stop lights since there isn't natural airflow blowing through.

Your best bet is to get something like a scangauge2 so you can monitor your coolant temps and see if the fans should be turning on or not. Otherwise you're taking a wild stab in the dark and have no way of knowing what's going on.

Scangauge2 is on the list.

Despite the 30mi drive it's the same situation as before which was 4.5 hour drive. Arrived turned off - no fans. Back to ACC - fans on.

I just changed my Thermostat(damn its a bitch to get it off!), didnt drain and flush this time cuz the coolant is very new (like less than 100 miles), so I just top it off and bleed the air out.

Gonna test it soon, see if it helps the heating problem.

Turn a/c on when running, fans should stay on.

I know many cars do this, but the 8 does not - the fans are strictly controlled by coolant temps and are not automatically turned on with the AC Compressor.

I cannot recommend highly enough the Mazsport Cooling Fan Mod - I have had it for 1.5 years and it works great. While it will not actually increase your maximum cooling capacity, it will get the most out of it and will keep you average engine temperature much lower during normal operating conditions.

Have had the Mazsport Cooling mod for two weeks now. Everytime I pull into the driveway coming home from work (only 5 miles) my fans are blowing hard! I love it!!! It makes me confident that there was something messed up with one of the fan relays. I'll probably go have them tested just to see.

Rythmic, don't delay and pick one up now!

So can anyone confirm what the Cooling Fan 3 relay is for?