Overheated. Temp gauge fluctuating. How long do I have?
 

Hi everyone. 2007 JDM Automatic with 30,000 miles here. New plugs, coils and wires. No mods.

My steering feedback was a little numb so I got the power steering connectors cleaned by my mechanic 2 days ago. Cleaned the torque sensor as well.

While I was driving home, i was in manual mode with the revs up. I noticed that the AC wasn't cool enough. It was like on and off. It got cool for a 5 seconds and then didn't for 5 seconds. Kept doing that continuously. I then noticed that my temperature gauge was going up. I had to stop at a red light and it went even higher! Pulled over immediately. Kept the engine running and the temp gauge got really close to H. It was around 4 clicks from H. Went back to my mechanic. Weirdly, when I started driving, the temp needle went back to the middle. I was in auto, just cruising at around 30mph in 5th/6th gear and everything was good. I then stopped at a gas station to get gas. Stayed there with the car running for about 3 minutes and the temp went up again! :( I finally got to my mechanics house. He tried flooring it at idle. The temp went up, and then after a minute, went back down again. Again after 30 seconds it went up. After 30 seconds, went back down!! It kept going up and down. It was fluctuating. He said it should never fluctuate. And the temp should never go back down within 30 seconds.

At first he thought it was the water temp sensor. But all we did was clean the Power Steering connectors. We took the battery out and examined the fan underneath it and the connector to the fan was burnt. There was coolant overflow on the connector as well. It didn't blow a fuse either. Because it didn't blow a fuse, he thinks that it must have killed the fan motor as well.

On my way home, everything was fine. Floored it at times. Power was good. Kept it in auto so it was mostly in 5th and 6th. AC was good. The temp gauge was one click below the middle. Everything was great! The temp gauge didn't move a millimeter. I came home, turned the car off and the fans stayed on for only 3 seconds. Everything was good :/

It's 95 degrees over here with crazy humidity. On my way to the mechanic, the ambient temp was reading 102 degrees! Never seen it go that high before though.

When my mechanic floored it, slightly blue tinted smoke came out of the exhaust. Wasn't a lot. But noticeable. My cat is gutted as well. Maybe oil is leaking into the engine? Oil level was a little low as well.


All that said, the needle moved. So the damage has been done and I'm expecting the worst. Coolant probably leaked into the engine. My question is, how long will this engine last?

Thanks

O k first off its a good thing in this car for oil to be missing the engine burns it. Next if you haven't had a failure of your coolant seal your lucky you should have turned it off as soon as the gauge moved it's never a good thing to run these things at all when getting hot. Have your cooling system pressure tested that will tell wether you killed the seals or not. Second get what ever the reason your over heating is fixed.

If your water temperature gauge crossed the 50% mark then the damage is likely already done.

No one can give you a difinitive answer on how long the engine will last. It really depends on how much damage was done with overheating. You could be lucky and have nothing wrong. Or which is more likely the overheating warped parts of the motor and it will lose compression here soon or just piss coolant into the motor.

Look at your cooling fans....likely one isn't working

Usually if there is damage it will leak or not start after. You might be OK...just don't let it overheat any more.

Time will tell...keep your fingers crossed :)

Thanks for all the advice guys. I got my fans checked and all I can say is, I'm REALLY UNLUCKY :(

After cleaning the steering wheel connectors 3 days ago, my mechanic put the air cleaner box in. It wasn't easy so he wiggled it around quite a bit. While doing so, one of the rubber bushes at the bottom had fallen off and got stuck in between the fan and the radiator :(

Today I took the car to a different mechanic, who is a friend of my dad's and got this checked. This is how I found out what had happened.

As soon as we took the air cleaner box out, we noticed that one rubber bush was missing. Put a light in there and saw that it was on the radiator :( it was under the fan that's directly under the coolant bottle (passenger side in the US).

We hooked the fans up to a battery directly. Both fans work.

It didn't overheat today. Left it idling for 30 mins. No problems. On my way home, I drove it fairly hard. It did not overheat.

Much more common than you think .....hopefully you are good :)

Hi. Thanks :) hopefully!

What's more common?

This is what fell off. You can see that on the left side it's missing and on the right side it's there. I've circled where it's missing :)

LOL...the grommet in the fan problem :) You aren't the first one who had the problem...and likely won't be the last

Not a very inspiring design for those grommets when they can toast your motor when they fall out

If you get overheating when you are stationary....and not when you are driving....the fans are the first place to look. A failing water pump or thermostat will overheat more at speed usually because of higher heat loading on the engine

Good to hear you found your problem and suffered no engine failure due to over heating it. Just remember if you coolant gauge starts to move past normal shut it off because your already in danger of loosing your engine.

Dannobre,

Haha yeah it's crazy. I mean who would've thought so!

Oh but I did :D

https://www.rx8club.com/showthread.php?t=45395

Read that yesterday and I knew that it must have been it. Because we took the air filter box out. That was the first thing to look when I took the box out. However, I was expecting to see a burnt fan!

Niteshade247,

Thanks a lot. Yes. Hopefully it's fine. But I've read that if I'm overheating, I should NOT turn off my engine as it'll stop the airflow, increasing the heat!

So I don't know how this car overheated. Maybe that rubber bush got stuck while I was driving home after cleaning the connectors, and when I stopped the engine, since the fan stopped, it dropped down to the radiator and just stayed there? Because my car didn't overheat one bit on my drive home.

If it got stuck, why didn't the fan just call it quits? Why didn't a fuse blow? :/

If you are in a hot climate zone, then look into Mazmart's Remedy Thermostat which opens at 69 or 72F not sure. Also, the fan mod, to trigger them at lower temps instead of factory settings. They will help you tremendously going forward. Also, look into throttle body bypass mod.

all the best

your fans only run when the car is stationary, or near stationary. The hypothesis is that you overheated at rest, not while moving.

Otherwise...

Let me clarify. If your over heating and driving down the road get off the road and shut it off as driving is only going to increase the problem. If your only over heating when stopped yeh keep diving till you get home then shut it off and find out what's wrong. The difference in the two is over heating when driving is more than likely due to radiator, thermostat, hose, or some other coolant failure and not shutting down is only going to make a bad thing wors. Over heating when sitting still is most likely a fan issue and you need to drive to get air in the rad to cool off.

Thanks a lot for the replies guys.

Kurrham,

I did look into those, but I'm afraid of messing with them and screwing something up :( and causing MORE problems. I have however, decided to get water temp, oil temp and oil pressure gauges to mount on my ashtray.


ShellDude and niteshade247,

Yes, that's exactly why I kept driving. But I still don't know what happened. Did the rubber grommet get stuck and jammed the fan? If it jammed the fan, why didn't the fan just die? It didn't even blow a fuse.

On the day it overheated, I drove right back to my mechanic and stopped the engine, after I fired it back up, it did not over heat.

My only explanation is, the grommet fell onto one of the fan's blades while putting the air filter box in and jammed the fan. Overheated while I was driving. When I got back to my mechanic and stopped the engine, it fell down to the radiator. Because when I found it yesterday, it was just on the radiator. The fan was able to spin freely. So it wasn't jamming it yesterday. But still, if my car was overheating, it MUST HAVE jammed the fan at one point. Then why didn't the fan burn out? :/

Weird stuff :/

UPDATE!

I plugged my OBD2 scanner and went for a drive (cheapo $8 eBay scanner). It was mostly a city crawl. I noticed that my temps were around 204F when idling. It goes up to about 208F when driving (slow 15mph traffic). I floored it twice to get up to 35mph and my coolant went up to 212F! It didn't go higher than that though. 5 mins later I stopped and while it was idling, it went back down to 204F.

Is this normal? The car was showing 91F on the ambient temp display.

I see these temps in traffic wouldn't advise doing fast bursts like that though. So to give you your answer I would say yes it's normal with no cooling mods done. Mine runs about the 200 range in city with out side temps 85 to 100.

Thanks for the reply. That's good to hear. I was thinking my thermostat went bad after the overheat. Or maybe my water temp was failing (since the temp went up when I floored it). I'm gonna try blocking the area around the radiator as advised on the $100 thread.

But if the temp went up to 212F while just flooring it to 35mph twice, wouldn't it overheat if it kept the revs high doing 20-50mph? Because that's exactly what I was doing on the day it overheated. I was mostly in 1st and 2nd, shifting at around 5000rpm :(

Just to let you guys know, this is how high my temp gauge climbed.

You got lucky big time. The thing with doing 35 mph sprinting in traffic VS Highway is air flow to the rad in traffic you have to stop on the highway you can continue going to faster speeds letting more air run through the rad. I would think that yes you could over heat a perfectly good cooling system by doing low speed sprints as again the air flow is limited.

Damn. It wasn't in traffic though. The roads were empty. I was going at around 40mph most of the time. I'm still trying to figure out how my car overheated all of a sudden. I currently have 2 theories. 1) The grommet falling in and jamming the fan and then somehow falling down to the radiator, causing the fan to spin again. 2) the grommet was always down there on the radiator, the car just overheated coz I was having the revs up. If it's number 2, I'm in for a big bill :(

Also, if the grommet blocked a fan, it would've at least blown a fuse, or killed the fan motor.

Woah..You got lucky there..

+1 on what niteshade said.

Definatelty look into cooling mods.

Friendly advice flush you system change your thermostat and coolant bottle. If no change then new rad as well get the fans to kick in sooner.