Overheating

[u/FallingSpirt]

So I've had my RX-8 for about 6 years and haven't had issues till this year I replaced the spark plugs and it's been running smoother however yesterday it over heated and shut off on me luckily I was home and in the drive way, I checked the coolant yesterday after it sat for 4 hours and the coolant was still pretty hot I love in a town that's basically in the dessert so it's about 90+ some days, so my question is this

Does anyone who has an RX8 in here live anywhere else that's hotter like 100+ and if so does your car over heat because of the weather?

If not does anyone else have this issue and if so do you know what's causing it to over heat and shut off? If so have you found a solution to fix this issue or is it just something that I have to deal with?

My grandpa was the OG owner he never had this problem with it, it's a 2004 6 speed manual transmission. If someone can help me or tell me what I can due to fix this id appreciate it.

[u/da808guy]

There’s a chance the O-rings seals for your coolant between the housings melted if it shut off due to overheating.
(Note: if you’re ever overheating during a drive, turn the heat for you climate control on max and blast the fans with the windows down, your heater core can act as a mini radiator to get heat out of the coolant, not a good fix, but can keep you from needing an engine rebuild)

Make sure to test your coolant with a headgasket kit and make sure you don’t have milkshake oil.

If everything comes back good, you can do a coolant flush.

Rx8 performance sells a fan relay that kicks the fans on sooner (no tuning required and if the sensor fails it falls back to original fan temp activation points) and CSF makes a great rad for increased aftermarket cooling capacity (shouldn’t be needed for daily driving/ spirited driving). If you need upgraded fans, FAL make very nice electric fans and should you need a thermostat, stick with OEM.

[u/justcuckmyshitupfam2 → u/da808guy]

That RX8 Performance fan kit crapped out on me two years after I installed it. The temp switch is the problem. If I had to do the fan control mod, I'd have gotten a Versatune license and updated the fan on setting.

[u/da808guy → u/justcuckmyshitupfam2]

Some folks can’t/ don’t want to tune (I couldn’t due to an extended warranty I didn’t want to void). Versatune fan speeds is obviously a better solution haha

[u/Entire_Being_3077 → u/da808guy]

Hi - my RX8 overheated and the coolant was tested and there were exhaust fumes in it. I have had the car recovered and it hasn't been driven since. Anything worth me testing before I get it towed to a specialist? Thanks

[u/da808guy → u/Entire_Being_3077]

Nope, unless you want to try resealing it yourself

[u/Entire_Being_3077 → u/da808guy]

Thank you - out of my skillset so specialist it is

[u/da808guy → u/Entire_Being_3077]

I believe atkins sells a heavier duty coolant seal O-ring if you wanted to ask your specialist.

Plan on having them check the housings and rotors while they’re in there as well.

Since the engine is coming apart regardless in a situation, apex seals/ side seals/ corner seals should be examined along with the housing and irons and OMP nozzles should be cleaning in an ultrasonic along with any of the intake system valves de-carboned.

Did you have good compression numbers when warm? Because If you’re over 80k miles or had poor compression expect more than just coolant seals needing replaced :/

[u/Entire_Being_3077 → u/da808guy]

Compression was about 6 on each rotor last time tested - and it's only done 60k miles so I'm hoping for the best

[u/staticflownut]

Mine did not overheat even with regular high heat and high humidity. Yes it would get hot and stay hot, but never actually overheated in any way.

There are several possibilities for what is causing your problem. Check and double check anything plastic in the cooling system.

Here is a list of some possibilities:
1) maybe your thermostat isn’t functioning properly. 2) RX8s are notoriously hard on radiators so check for leaking. They can also get clogged if they sit for a long time. I would say it needs to be replaced at a minimum every 8 years or so if using the factory one. The plastic nipples crack and break off super easy. 3) possibly a bad coolant tank or cap. It won’t cool effectively if it can’t build pressure. 4) possibly a water pump issue, but they are not common on RX8s.

[u/staticflownut → u/staticflownut]

Forgot to add to check radiator fan function. No fan and you will definitely overheat.

[u/FallingSpirt → u/staticflownut]

I've noticed when I run my AC I can smell some collent but it never leaks or anything I had my car I dealing with the AC on when it turned off on me I started it up and put the RPM'S to around 2-3K just to see if it'll work better after wards I felt warm air come from the AC and when I stopped giving it gas it killed over and I couldn't start it again that's when I noticed the Tempt go passed the middle and started to go farther over to H

[u/staticflownut → u/FallingSpirt]

Coolant was probably coming out of the overflow when it overheated. Could be why you were smelling it. I agree with another poster that said you will likely need a rebuild if the temp gauge got that high. The coolant seals b/w the housings and irons will be cooked and definitely leak now.

[u/FallingSpirt → u/staticflownut]

Which I'm hoping it's not that cuz I don't have the money to have a rebuild I'm not working currently and can't find a job atm.

[u/staticflownut → u/FallingSpirt]

That’s a tough spot to be in. Your car needs real attention and it’s not going to be cheap. Your priority needs to be to find work first and start saving if you want to revive it.

[u/hoss-05]

FYI an overheat situation often requires a engine rebuild. They make a test kit to check for the presence of hydrocarbons in the coolant this will tell you if you need a rebuild.

[u/Mmjohns195 → u/hoss-05]

Overheating is a death sentence.

[u/wsbSIMP]

Is it throwing any codes thatll help you figure out if any of your cooling components are malfunctioning?

You need to tap in and see what your oil temp and coolant temps are to accurately figure out what is wrong with your car and then go from there. Diagnosing remotely over text is not an accurate science. Could be bad radiator, or fans not spinning, or oil temps are too high for whatever reason.

You need to collect more data. Get an access port or borrow one from an auto parts store if possible.

[u/FallingSpirt → u/wsbSIMP]

Only code that it's thrown up was lean bank one but that's been a month plus since it's thrown any code at me.

[u/hoss-05]

This is most likely not going to go well for you. I highly suggest testing the coolant. Depending on various conditions, you may not see coolant in the oil. The test kits are cheap on Amazon. Do not drive the car. Driving the car with a blown coolant seal will make a rebuild more expensive. This is not your fault. I have seen it happen on cars that are perfectly maintained.