Engine Overheating?
 

I am having a problem with the engine overheating and the coolant leaking whenever I am stuck in a traffic jam or moving too slow. The first garage I took it to (Pep Boys) told me it was the radiator cap which I duly replaced, now after a new radiator coolant reservoir and cap later I am still having the same problem. After doing some reflecting I am thinking this is due to a fan outage as the engine is cool whenever I am on the highway doing 80mph or so, but only has problems when moving slow/stuck in traffic for extended periods of time (which can happen a lot in Puerto Rico).

So my question is this:

Does the RX8 have a fan that is supposed to kick in and keep the engine cool at low speeds/not moving?

How much does that fan cost to replace?

And lastly since I am not a mechanic does the above (self diagnosis) sound correct? (I cannot hear any fan running after I shut the car down). Has this happened to anyone else?

-Thnx

Dilip

Yes the 8 has a fan that should come on when it is getting hot and it should come on when you are stopped and/or after you shut the car off.

I am no mechanic but maybe a blown fuse or loose plug?

I'm dealing with some overheating issues myself.

The fans are programed to kick on automatically at a certain temp (200F ish, someone else will probably correct me with the exact temp)

The point is that if you leave your car idle, the fans should kick on after a few minutes.

The quick test to turn on your Air conditioner, this should overide the temp stipulation and, if your fans are working, turn them on. (Not positive, but pretty sure)

However... your fans not working doesn't match the symptom you have of a coolant leak under high temperature. Water cooled systems work because water under pressure can retain alot more heat than water not under pressure. When the system loses pressure (leak) the rest of the fluid in the system is allowed to expand properly and rendering your coolant system essentially useless.

Find out where your leaking your hot coolant.

Again, let your car idle in your driveway or safe place, observe if the fans kick on with the AC or because of temp. Then (wear safety glasses, gloves, and anything else that will protect you from burns) and begin to trace where you may be leaking from.

Again, fans alone won't cause the system to leak.

Hope this helps.

There are 2 fans behind the radiator. Both have a low and high speed mode.

it depends on the coolant temp, I think it will start with low speed mode when it sees 97 Celsius. and Full speed(high speed) at 102 or 103 Celsius.

To test your fans you can use the relays. but if u're lazy or dunno how.

AC and heater off, idle your car at 2K rpm, have someone stand in front of your car with the hood up of course, fan will kick on at 97 Celsius. keep it that way for a while, then it will go into high speed mode, the sound of high speed and low speed are very different so u should be able to tell if its working like that.

if it never goes into high speed mode or fan doesnt come on at all, you have a problem, it could be a bad relay, bad wiring, bad ECU, or just dead fan motor.

Another reason for boil over is, you have air in your system. You need to bleed it out(or burp it out).

how?

park ur car at incline with nose up. make sure your coolant level is at "Full" mark. start your car and let it idle, u see that temp. needling moving to the center right? when it reaches the center, go check and see if u lose any coolant, if u do, add some to make it back to the Full mark. then close the radiator cap. Idle your car at around 2.5K RPM for 10 minutes (your fan should kick on at this time), then let it go, and Idle at 3K rpm for another 5 minutes or so. keep checking to see if u lose any coolant but DONT OPEN THE CAP AT THIS TIME. Turn it off and let it sit there for at least an hour or 2. then come back and open the cap slowly, then add coolant. and repeat until you're not losing any more coolant.

. . . . . The leaking is boil over :pat:

Ignore me. . . i'm still a noob apparently.

Thanks for your help guys, and yes the leaking indeed was boil over. (It leaks from the pipe on the side of the reservoir). I took it to a garage as icould not hear the fans working period and it turns out it was indeed 2 dead fan motors. It looks like it is going to cost mr $561 in parts (Fan Motor Assembly) and $165 for labor. Does that sound reasonable?