I'd like to start by saying I've owned the car since it was new and put almost 100k miles on it in 5 years. as well as I've been a RX8club member almost the entire time and know how to search. My engine just lost compression and I just got a new engine put in this week.

The first day I brought it home it was about 60 deg out and raining - the fan started when i turned the car off, no big deal i thought.. it's normal after all. I went on inside and the fans had stopped when i check it about half an hour later.

Turns out that the 40A fuse had blown, and that's why the fans turned off, I didn't realize that till 2 days later when i was sitting idling and saw that temp spike up

Got the fuse replaced, and today it was 45-50 degrees out, I am not driving the car hard (breaking in period on the new engine) and the fans are running 10+ minutes after I turn the car off every time.

I haven't done the turn the ignition on and off to get the fans to go off, because I'd rather find out what's causing them to stay on when it's not hot.

If you guys have any ideas please let me know.

 

a bad relay?

 

I have only a very basic understanding of how a relay works.. could a bad relay case that? if so, is it a relay in the main fuse box under the hood?

 

Hope this helps.

-Shawn

 

the fan spins based on the temp reading from the sensor behind the thermostat housing.

so make sure that part is working. and you will be good.

also, please make sure your thermostat is NOT stuck.

 

basic thing but :
have you checked the coolant level ?

 

@brettus - I haven't personally checked the levels, but they just put the new engine in this week, and they had to refill the coolant when they did that. As well as taking it back today when it overheated (i was already in town) and they told me the fuse had blown. I also assume they would have checked it then. I'll check it tomorrow to be sure.

@1.3liters - I can't understand those.. (i'm more of a car audio guy than a car electrical systems guy) can you explain?

@nycgps - Is that the same part that gives the temp reading on the dash? if so, it is working normally, shows normal temp except for today when it started to overheat, which it indicated properly.



If the relay was going bad would it cause my problem?
and after this post when i drove to the store it started blowing again, a ignition on and off did turn the fans off. if the temp sensor was messed up would it turn off or keep running?

 

A new engine takes a while to purge out all the air in the system . This does sound like an installation problem that you should not have to deal with to me.

 

question : who replaced your engine ?

 

@Brettus - if I can't fix it, or it doesn't get better, I'll take it back to them

@nygps - Nelson Mazda - Antioch, TN. The same place I bought the car and have taken it for regular maintenance, they seem to do good work and I like the people in the service department

 

According to my manual...

"Cooling fans: Operates when PCM determines fan operation depending on Crankshaft Position, Engine Coolant Temperature, Vehicle Speed, Intake Air Temperature Senors, and A/C switch, Refrigerant switch inputs."

Sounds like a stuck relay, next time it happens (and you don't think they should be on), give the cooling fan relays some light taps and see if the fans go out.

 

Thanks for your help guys, I'm going to change the relay out tomorrow. I'll post whether that fixes it or not

 

Swapping out relays didn't help. I took to the stealership and they told me that the motor on fan 2 was blown. They replaced it and everything is working normal now. Thanks for helping me out guys.