so my little brother got a rx8 a few months back and his coolant light comes on but his coolant will be topped.. I know his sensor has been shot but they r trying to charge him 350! For jus replacing it..my question now is if he leaves it like that will he be fine since its jus the sensor?

 

teach him how to replace it himself

 

It's actually the float, not the sensor. If you want it to work, the tank needs to be replaced. The part is about $100...at least that's what it was a couple of months ago when one dealer was having a sale. There's a TSB on the subject. If you replace it, you need to be careful about breaking the radiator when removing one hose.

Easiest solution is to unplug the wire to the sensor, and visually check coolant level every now and then.

Ken

 

I would get it fixed correctly. The "easy fix" sounds like a good way to blow an engine. The temp gauge is very slow to show your over heating.

 

Install aftermarket temp. gauges. You should really have them anyways if you really want to monitor temps. and pressures.

 

Just replace whatever is defective, the thermostat, the sensor or the float. If you leave it like that, how will you suppose to know if your coolant needs refilling or it's leaking or your engine is overheating. Just replace it, so you have peace of mind.

 

yea im going to replace it forsure. Im thinking of replacing it myself though since the dealer is trying to get him for $350

 

The coolant light isn't a temperature gauge. It's a coolant level indicator. I don't know how common it is for cars to have them these days, but the 8 is the first car I ever owned that had one.

Coolant level is one of the fluid checks you should make periodically. Kind of easy to do with a translucent tank like the 8 has.

Ken

 

Ever had a hose break while driving? You would never know cause the light doesn't work. And the temp gauge on the rx8 is a dummy gauge, in another words. You would already be over heating before the gauge responds.

 

Yes - I've had a hose or two burst. There's usually a big gush of steam and hot water as the coolant sprays around under the hood.

The temp gauge is not a dummy. I understand that it's not particularly linear, with a big flat spot in the middle, but it's not an idiot-light equivalent the way that the oil pressure gauge is. Hopefully it's adequate to warn about overheating if the water pump fails or the thermostat sticks. Those are events that have happened to me more often than burst hoses.

If the coolant level light works, it's of some use. I did have mine alert me to low coolant level once, when the car was about a year old. Low enough to go off, not low enough to be a problem. Now it's doing the intermittent on-for-no-reason thing. If it worked and was reliable, I'd be happy to have it. But if it dies I personally don't think it's worth the investment to fix. Like I said, I've never had this kind of light before.

Ken

 

Ive blown radiator hoses while driving, it smells horrible too. Dont forget that part lol.

 

Key word here is "usually", unfortunately that's not always the case.

From my experience, its 100% crucial to have. My last car (2004 Grand Am v6) had the "low coolant light" (btw almost every car has one). On my way to visit my family for Thanksgiving (2008) my head-gasket began leaking (I know I know we don't have HGs, but we do have coolant seals), I had no clue. The "low coolant light sensor" apparently broke sometime between me buying the car new and 2008, but not like the Rx-8 does, it broke where it never registered it was low on coolant (Just like the "quick fix" for the Rx-8). Luckily for me, the cars temp gauge was a real one and moved all the time. I caught the problem before destroying the engine completely (by seeing erratic temp spikes) .

The Rx-8's coolant temp gauge is not the same. Using Live data feed on mine it can go AT LEAST to 222*f and still not move (I do not know at what temp it does begin to move cause the car started cooling down on it's own). But if your at +222*f with low coolant your asking for it. Why would anyone risk a 5k investment (new engine price?) to save $100-200 on a part that a 7 year old can change?

Also, think about this, if you lost all your coolant (or at least enough to have a large amount of air in the system) that temp sensor has nothing to read, making it useless.

And I feel your pain on the light coming on and off, mine does the same on hard acceleration. Mine goes away if you let the rpms return to idle for a moment though.

-Shawn

 

Never saw one until I got the 8.

Mine is different. It will come on while driving at steady speed, nothing in particular triggering it. It will then go off, not correlated with anything in particular.

No pain involved...I find it entertaining. I like to make up stories (e.g., "It's a Greek temple - the car wants us to stop for a gyro") if a passenger sees it.

Sounds like a real temp gauge is more important to have. Like I said, I've had more overheating incidents from stuck thermostats than from loss of coolant.

Ken

 

8 out of 11 of my cars had the level sensor

But you are right, an accurate temp gauge would be best.

 

Monchie.................you can't just replace the float!!!!

Haze310, if you want to read.................. https://www.rx8club.com/showthread.p...light=greatest

Then buy one at http://www.finishlineperformance.com...cat=336&page=1


1.3_LittersOfFurry, you are way paranoid!
What the frig do you think people did before they started putting those sensors in there?
I agree with Ken!!!!!
FYI..............do you let your low oil light come on before checking the oil?

 

^ That's why i put the float at the end of the sentence because i don't even know if you could replace it or not.

 

Me, Paranoid? Never. But I would accept OCD.
I just think it's retarded that someone is going to go spend a lot of money on some good gauges to read their coolant temp and not spend $100 on a OEM Level sensor. It's there for a reason ya know. And it's only $100, I mean if your cheeping out cause of the price your driving the wrong kind of car.
Your risking a large investment (car) on something a 7 year old can fix.


They checked their coolant levels I've owned 3 cars without it. But it is on the Rx-8, so why not just fix it? Right?


I agreed with him too, to some extent...
I check my oil level every 2nd fill-up like the manual states to do , even though the Rx-8 barely uses any compared to all 3 Rx-7's I've owned.

-Shawn

 

I know the coolant gauge is a dummy gauge to an extent. It will show over heating but not read exact, but doesnt the coolant light also come on if the car is getting hot/overheating, not jsut when it is low on coolant.

 

Mines doing the same thing........going to have to use that story when someone asks about it

 

I hate for Monchie to actually be right about something - upsets the balance of the universe - but I recall a post by someone who did replace the float. Cut a hole in the tank, stuck in a wine cork, then plugged the hole with a couple of washers and a bolt and some rubber gaskets.

Ken

 

Was just razzing ya a little bit.
I agree with most of the points you made in response!
FYI............I bought the new bottle.......AND......I have aftermarket gauges.......OCD for me!


- Dave

 

I remember that...............way dicey and ghetto. At that point, I would unplug it or buy the damn bottle.

 

No.................level sensor only.
Now having said that, let's say you loose enough that the level drops, the float will drop, and therefore turn on the light.
So.....being ****, I use the light to monitor the level................although I'm under the hood three times a week anyway, so I visually check it while there. Then I have aftermarket gauges and monitor the actual temp, therefore I rely on that pretty much 100%. Gauge has warning levels I can setup to alert me if it's getting above a certain preset temp.

 

Is the coolant light sensor and the coolant temperature sensor the same sensors... or no?

 

Thanks for backing me up. I know it's a ghetto way to do it, but it works