So i was drivin home yesterday, 30 mile drive, and about halfway there the "add coolant" idiot light blips on w/that annoying buzzer and then back off...just blipped like that (by blip i mean about 1/2 a second) twice more before i got home. When i did get home, checked my overflow bottle, and it was above the fill line...obviously don't need anymore.

I start driving to my g/f's tonite....same drive, and about halfway there it blips on/off once, then comes back on and stays on. I pull over on the freeway and check it, coolant is still above the fill line. At no time did the temp gauge budge at all. What could this be?

1. bad thermostat?

2. bad radiator hose?

3. or worse somethin i don't even wanna know.

Since it's saturday and tomorrow's easter i'm sol to see my mechanic until at least monday, if not later. My only other vehicle is an F-350 gas guzzler, that i really can't afford to be putting gas into . Any ideas or tips would be nice. I've tried to be as detailed as possible. My mods are hks catback and bonez intake system. In the meantime i'll search and try to find some answers, but haven't found much yet.

 

could just be that you need to have your idiot light cluster resoldered. Or your CPU resoldered... or your coolant could just be a smidge low causing it to barely miss the sensor???

 

did it turn on during cornering? It can move around and trip the sensor. Also, if I recall correctly the same buzzer sounds when the oil level is very low. Might want to check that as well.

 

Obviously? The warning light it warns of low coolant in the radiator, not the overflow bottle. Top up the radiator and make sure you get all of the air out of the system. If it does it again start looking for leaks.

And be careful referring to them as "idiot" lights...

 

'86GXL- Coolant is above fill line, so can't be that...cpu a possibility

Pure - Going out to check oil level now, although i'm still about 1k short of an oil change.

Any more ideas anyone?

 

NZ - also remembered that when i pulled over and put my hand over radiator cap (not overflow) that it wasn't very hot at all. Will open cap and release pressure to see if that helps.

 

archive has a good thread about filling up coolant to make sure there aren't air bubbles

https://www.rx7club.com/2nd-gen-archive-72/filling-coolant-after-rebuild-383818/

 

As NZConvertible said you checked the RAD to right? we dont care if the over flow is at proper amount that means nuthing of the posability of the RAD being low. check the fill cap on the RAD and the uper hose. The angle on the uper hose does not allow filling from there and vise versa on the RAD so you have to fill each unit. Then run your car to normal operating temp and let cool complealt. Now recheck and fill units if neccisary, your coolant is now toped off.

The car in my SIG that is sold started doing this other day. I do not know if it is related to this but it turns out the kid overheated it and killed a coolant seal in the #1 rotor housing. After that that buzzer and lights does what yours is doing. Perhaps someone smarter can shed light onto this.

 

Yah lets not talk about coolant seals i don't want any bad vibes...lol

Have checked all and filled all, i'm going to let it sit over nite and see what it does tomorrow since i'm off. I have never overheated this car in the 5 months i've had it and this just started yesterday so we'll see...

 

Actually it can't. There's a 7 second delay built into the warning system, so if the buzzer sounds going around corners it'll definitely be the low oil warning.

 

well i added oil and coolant to all places suggested, so we will see what happens when i'm drivin around tomorrow

 

Coolant above the fill line??? you must have missed read what was posted earlier... The buzzer and warning are for the radiator, Not the coolant over flow tank. The over flow tank has a fill line, the radiator does not. You have bubbles in the radiator, not the over flow tank.

And the CPU (as well as the ECU) would have nothing to do with the buzzer.

 

nz posted while i was replying, so i didn't read his before i posted immediately after him, so i figured that out after that, but thanks anyway

 

How old is the radiator cap? Old caps don't old pressure and will produce the results you are seeing.

 

don't know...i've only had the car for 5 months....doesn't look old, but still could be the original. Would it all the sudden start causing problems though 5 months later out of the blue?

 

Check the ground wire connected to the Cooliant level Sensor (the hexnut shaped bolt looking on top of the radiator) if its not grounded properly then reground it with some 10 or 12 gauge wire somewhere on the frame of car.


Blvd

 

Don't look for a formal letter of impending failure from your radiator cap. If it's the original cap, its trash. Radiator caps, hoses, belts, coolant, water pumps, thermostats and radiators are all consumable items. Over time they wear out and must be replaced.

According to Stant (one of the world's largest manufacturer's of radiator caps), caps should be tested and/or replaced whenever the cooling system is serviced. According to the 1989 Rx-7 Owner's Manual, that's once every thirty months or thirty thousand miles, whichever comes first.

 

That is not a ground wire and it should not be grounded! Jeez, where do these ideas come from?

 

What you honestly don't know? they're just making **** up as usuall

Its amazing how people with the misinformation can sound 100% correct to the person that doesn't know. Too bad we couldn't just label their whole text box and avatar with a dark blue. So whenever you see a post by them, its all blue and it says "bullshitter" so we can filter this stuff out

Damnit, im goin to bed...

 

Quote:
Originally Posted by NZConvertible
That is not a ground wire and it should not be grounded! Jeez, where do these ideas come from?



"What you honestly don't know? they're just making **** up as usuall

Its amazing how people with the misinformation can sound 100% correct to the person that doesn't know. Too bad we couldn't just label their whole text box and avatar with a dark blue. So whenever you see a post by them, its all blue and it says "bullshitter" so we can filter this stuff out

Damnit, im goin to bed..."



That's good!
Actually, it would solve his problem, in a way. Not a good way mind you, but it wouldn't buzz anymore.
And in a sense it is a ground wire. It's just that the coolant is the ground. No coolant = no ground. Then the buzzer.

As an answer to the original post. The overflow has nothing to do with your problem. The most likely answer is that you have an air bubble trapped in your coolant system. OR, you have a small leak, like possibly the weep hole in the water pump (meaning,your water pump is bad). Either way you need to find out. Check the thread out posted above for "burping" the air out of your system. Also, check under the car for a small amount of coolant. If it is the weep hole it is hard to find. And the buzzer will only go off intermittently.

 

If the coolant overflow tank was not over filled prior to this event and the engine was not over heated then:

1. The radiator cap is not allowing the overflow coolant to return to the radiator. Replace the rad cap.

2. The return tubing between the radiator cap and the overflow tank has a hole in it. Replace the tubing. (The pick-up tube inside the overflow tank may also have a pin hole, but it will be above the level of the fluid in the tank).

Either 1 or 2 or both are the cause of your problem. To be on the safe side, replace both. Follow the FSM 'burping proceedure' to properly fill your cooling system.