Overheating!

[WWI Flying Ace]

Help! 2007 GXP...Car normally runs between 195-215, like clockwork. Even in summer. Then, out of the blue in September, I got my car back from the dealer (they replaced the fuel rail because it was bad) and it was great…ran like new again (zoom zoom in a way Mazda will never understand)…but then, on the way home, the temperature surged, up to 255 degrees! I used to have an MGB, luckily, so I have a couple tricks to use when a car gets too hot…(heater on recirc high despite the summer temperatures) and it went away…temp dropped quickly and then was normal. Then fine for months…then, about 2 months later, same thing, got in the car after work, started the drive home, 5 minutes in temp surged to 250-260 again…again, I did the trick with the heater (it is a super temporary thing but it will bring the temp down a few degrees)…and then whatever was wrong stopped, and it was fine…till tonight. Tonight, third time, same thing. Since it was winter I was waiting for he heater, and it was blowing cold. Temp went to 256, and I was looking at going to sit on the side of the road while she cooled down…but again, after about 10 mins, whatever was wrong stopped and the temp normalized.

I am thinking thermostat? Or is there a TSB that people know about? Was taking her in for oil change and tire rotation next week anyway, so this will be on the docket…but is there something that people know about that I should alert them to look at?

[shabby]

Sounds like the thermostat, but good luck trying to duplicate the problem at the dealership. Last time this happened to me i took a video with my phone and only then they decided to change it.

[typhoon]

Sounds like air trapped in the cooling system. Or, I hate to say it, a bad head gasket can pump air into the cooling system.

[DaveOC]

I was thinking air trapped in the cooling system, but that isn't very likely due to the highly intermittent nature, so I'll settle on a thermostat, a highly intermittent, occassionaly malfunctioning thermostat.

[Charlie W]

I got my GXP on 11/25/06. The first time it got close to zero the heater was working fine then started blowing cold air and the coolant temp. went up to 250. I was waiting in the drive thru at Arby's and before I could leave it went back to normal. It's never happened again and the car has well over 16500 miles and is two years old today. My guess is the thermostat stuck.

[silversolstice]

I don't know what changing the fuel rail would have done, but it seems like it was something the dealership just did.

I did want to say thanks for proving that the heater would bring the temp down. There was a thread months back where we couldn't figure out why the coolant temp increased when the heater was on(at operating temp), which contradicts conventional wisdom.

[WWI Flying Ace]

Originally Posted by silversolstice I don't know what changing the fuel rail would have done, but it seems like it was something the dealership just did. I did want to say thanks for proving that the heater would bring the temp down. There was a thread months back where we couldn't figure out why the coolant temp increased when the heater was on(at operating temp), which contradicts conventional wisdom.

Sure...its a handy trick...Standard Operating Procedure for MG/British car ownership.
The heater core acts like a second, smaller radiator. When you run the heater on recirculate, you are running the coolant not only through the car's radiator, but also through the heater "radiator", thus cooling it just a bit. Not much but enough to take the edge off. Has to be on recirc though...or it won't work. And it is miserable if you have to do it in the heat of summer!

There were other tricks with the MG (and for any older car), like revving the engine...it is counterintuitive but when you rev an older car, the fan blows faster and moves more air over the radiator, and therefore you cool it more. But, I don't think that works with newer cars.

Anyhow, I'll have to try and convince them to check the thermostat I guess...hope that's what it is, considering the other things that may be wrong!

[chuckdoc]

I posted about the same problem. Never got a conclusive answer. Now I am getting a intermittent picture of a radiator light. Just flashes on for a second and then goes out. Very intermittent. There was a two page thread on the same thing a while back but never saw a resolution. Morpheus had a similar problem but again, never saw a resolution. So many cars have posted on this it maybe should be a sticky post.

I also think someone had the coolant sensor replaced.

For some they just have the temp go high every couple of months, some get the low coolant warning plus temp and some have had a water pump failure occur.

It is too early to know if the thermostat is the problem because even after it has been replaced, it is so intermittent that not enough time has passed to declare a fix.

I really think all these are related problems. Unfortunately most dealers will just label it "unable to duplicate".

Owning this car is fun but it does remind me of when I owned a TR4. It was something every couple of weeks.

[Critterman]

Another trick learnef from owning a Brithish sports car, is proping the hood open an inch or so (rear opening only) until it cools down

[Gunnys GXP]

Mine does this also on occassion and it drives my dashhawk crazy when it goes over 116. I brought it up during my last oil change and they checked it out. They said everything is fine. The high speed fans are set to kick in at 230 degrees engine temp. I don't do the heater trick anymore. The highest mine has gotten is 244. They said 280 is the temp of death.

I still think it's not quite right that it would be so inconsistant to be normal and that there is an occasional thermostat "sticking", but a couple of quick stomps on the gas pedal to bump water pump pressure seems to be doing the trick for me. Only one time per day when it does it but it's an off and on occurance that started about 4 months ago.

[Hell Ride]

I would be curious to know (since I don't own a Solstice, yet anyway) if the fans on it are clutch or electric. If they're clutch type fans then I would upgrade to a set of dual electric fans. Replace the thermostat at the same time and hook those up. It's a great idea because they will spin faster and faster and not take any power from the motor to do so. I think it's your thermostat. If you had air in the cooling system then it would be overheating at idle too in some cases and you wouldn't be able to move the car more than a few feet without the temp gauge pegging. Oh and at the same time, change your anti-freeze to either Wetter Water or Royal Purple "Purple Ice". I swear by that stuff.

[Gunnys GXP]

Did some digging and found no TSB's relating to anything of this being an issue. YET.

[WWI Flying Ace]

Thanks for all the info everybody! I just made my appointment with the dealer for next Wednesday, and I am going to leave it there till Friday...so they have 3 days to look into this (and a couple other things I need done).

I'll mention all the info here when I drop it off, and also I'll come back and let everyone know what they say.

Happy Turkey Day to everyone tomorrow! Except any Canadians...in that case Happy Thursday!

[folkxrock]

Mine did the same thing a few weeks back. It might happen more often than I know because I am usually locked on the boost meter rather than temp.

[Gunnys GXP]

Originally Posted by folkxrock Mine did the same thing a few weeks back. It might happen more often than I know because I am usually locked on the boost meter rather than temp.

I am usualy on that also. It was when my Dashhawk started clicking and flashing red at 116 degrees that keyed me into it.