TailHappy

I'm stumped and was hoping maybe somebody has run into this problem before. To begin with, I took the car to have the clutch replaced. On the way home, the hose from the water cap at the center of the engine to the back of the AST popped off and dumped my coolant. The car never overheated, as I'm very vigilant in watching the gauge. I put the hose back on and after the car cooled off, I filled up the cap at the engine and the overflow tank. No more problems.

Then a few days later, the car started missing in the cold mornings when I'd start it. I also noticed a large amount of gray/white smoke in the mornings, but clears up after a minute or so. Doesn't smell like oil. Checked oil and water levels, both fine, and no evidence of water/oil mixture. Never any evidence of leaks under the car.

Couple of more days and less than a minute after starting the car, the temp gauge dropped to "0" and the buzzer started going off. I immediately turned the car off and pulled over. The overflow tank still had some in it, but the cap at the engine didn't have anything visibly in it. Should it? Filled that part up and the overflow again, and couldn't find it leaking anywhere. Same story this morning. Any idea what might be going on??????

Thanks in advance!

pweizman

Sounds like your engine is eating coolant.

The car might not have registered hot on the gauge, but it might have gotten hot enough to cook the water seals.....

Watch the coolant levels. Also, smell the exhaust, and see if it smells sweet like coolant.

Hope that helps.

Patrick

TailHappy

****! Not what I wanted to hear.....

Would the smoke go away though? It only smokes for about a minute after I start it in the morning and then it's all gone again. Generally isn't as bad after work. I started it this morning, rolled the windows down and backed up through the exhaust and it only smelled like exhaust. I get the occasional sweet smell of antifreeze inside the car while driving, but after the AST hose sprayed it all over the engine I just figured that'd be inevitable.

Can you overheat it when the temp hand never even got to horizontal (I realize it's not sensitive, but damn!)? It looked like I had lost the majority of my coolant after I parked the car that day judging from the size of the puddle.

Bucrx7

It sounds like you have air in the system. Try burping your system and see what happens. The reason your coolant buzzer is going off on cold start is because the filler neck is dry. I would top off your filler neck before you start your car in the morning until you can SEE coolant the next time you open it up.


Tony S.

pweizman

I think it is possible to overheat the car with the needle not moving.

It usually isn't likely though.

Maybe it is not as bad as I thought since you don't continue to get smoke.

I would make sure that you get the coolant filled ALL the way up. Make sure you get all the bubbles out of the system. Then get the coolant system pressure checked, and make sure you don't have a leak somewhere.

It could also be something simple like a bad coolant neck cap, thermostat or water pump.

Just be very careful, you cannot screw around with overheating your RX7. It is a very dangerous game to play.

Also, maybe you should check your plugs to be safe. Maybe the missing is just a fouled plug....

Later,
Patrick

TailHappy

Yeah, that's more the answer I was hoping for!

Sorry, but how do you "burp" it? I agree that I'm getting the buzzer because there's no water on the sensor, which I've verified by opening the cap at the engine. And I've heard that it's a pain in the butt to get the air out of the system on some cars once they dump their coolant. I have been getting by in the morning by filling up the filler neck until it's level with the cap and topping off the overflow. I'm just stumped why it doesn't fill that section up from the overflow tank, but I guess I'm really not that familiar with the system. Maybe the air keeps it from pulling it up the tube or something? Hoping that if I just keep filling it up the problem will go away..... (probably wishful thinking)

pweizman

Basically, if you keep filling it up, the air will eventually all get out.

What the manual says is to fill it, let it drain down, fill it again....then start the car and let it run for 5 minutes. Let the car cool, (really cool don't take the cap off the car when it is warm), fill it again. Keep doing this until the level of coolant doesn't drop down past the holes in the neck. If at any point the buzzer sounds, shut the car down.

I like to fill it, then wait a few minutes, and fill it some more. Air will work its way out by itself....I never like to start the car before I know that I have a pretty good amount of coolant in it. I have actually overfilled the car before too. This isn't a great idea, but it can't really hurt. It just overflows out of the top of resivour and makes a mess.

It is a long process. Either that, or try to reach down and work the bubbles out of the big radiator tube running under the airbox (hard unless you have an after market air intake).

Later,
Patrick

TailHappy

Maybe that's all that's wrong. I figured it would have tried to pull water from the overflow tank, but maybe the air in the system keeps it from being able to draw from there.

I agree on the plugs too. I just got the car a few months ago and just recently read about how frequently you have to change them. I have no idea when they were last changed, but I bought a new set this week and hope to swap them this weekend.

Thanks a bunch to both of you for your advice. I've read how many people have ruined their engines due to overheating problems and I don't want to be in that boat! Not an area I want to mess around in and accidentally do something dumb.

FD Seeker

Yeah, the gray/white smoke **** can really freak you out. Especially when it starts happening all of a sudden. My radiator went, and I got the low coolant buzzer etc... one of the things I noticed while trying to diagnose the problem was the smoke. I have no idea how these things would be related other than seals BUT THAT WAS NOT THE PROB. Like they said, as long as it doesn't smell like coolant... most of these cars create some smoke at cold startup which goes away in a minute or so.

TailHappy

Funny what you never noticed before once it becomes a symptom of another problem. I was the same guy that convinced myself that the fuel pump was bad one morning when it wouldn't start. I never noticed all the switching sounds and could have sworn the fuel pump hummed.....really the car was just flooded.

In this case it happened to get really cold outside right at the same time the hose popped off. This morning I drove about an 1/8 of a mile and could still see the smoke from where I started the car. Just got a little paranoid...what a relief!