Longhorn2806

Hi, I'm new to the forums, and would like to ask for some help with my (sometimes) overheating mustang.

I started a threat here http://www.stangnet.com/mustang-foru...ml#post8347341. The last post by me is a current summary of the issue.

I'm sure its not great Etiquette to have multiple threads going, but I'd like to see if I can get some extra eyes on the problem. I will be a responsible poster, and make sure to update both threads with the fix ... when we find it!

Thanks for the help! Let me know if I should re-post other information than the final fix here as well for some reason.

robb15033

It's easy. 1)Turn on A/C Max, fan should come on. If not, trouble shoot. If getting voltage and no fan, check fuses ect. ect.
2) Replace the thermostat to eliminate any maybe's. I am happy with my 160 deg even here in the snow.

Longhorn2806

Hey Robb,

Thanks for the comments. The thermostat and radiator have already been replaced. The fan also gets voltage and seems to come on at the right times. The odd think I need to look into more is why the car acts strange ONLY in colder weather (30-50 degree) vs. acting perfect in 70 degree weather.

I'd say the cold weather could be affecting the fan ground wire, except the engine overheats when doing ~50mph (where the fan isn't needed anyway), and when idle - the fan comes on at the right times. I'm really hoping its the sensor / sensor wiring. Whenever Texas weather decides to drop below 65, I'll be able to do some more trouble shooting.

jimkaray

How are you confirming the overheating? Is it running like crap, pinging - no power or is just the gauge reads hot? When you pull over is the fan running on high, the upper hose hot and full of pressure? If everything is normal other than the high temp reading then you've got a gauge issue or very likely an air pocket in the system that needs to be purged out.

NeoTokyo

Well I know my 95' has a Fan Relay right at the electric fan that 96+ didnt have.

Its possible that the relay is failing.

When my fan motor died in my 95' years and years ago it overheated no matter what if I wasnt moving.
I replaced it right away though.


+1 to jimkaray's question.

Longhorn2806

Hey Jim & Neo,

Thanks for the replies. Everytime it would get hot, I would rev the engine to cool it back down, so i never looked. Now that I know what to look for, I will actually pull over and note what is going on - fan, heat from vents, etc. It's supposed to get cold within the next few days (car only acts strange when its cold outside), so I'll post back ASAP after I have answers.

Thanks again for your input!

Longhorn2806

Jim - sorry, to answer you question directly - I have never been able to confirm it is actually overheating. (and the mechanic had a good question too: When the gauge reads "H", does the engine steam or anything? Answer: No.)

So, it is entirely possible that either the gauge is bad or a ground is lose. I lean towards the gauge b/c while driving on the highway, the temperature swing (from 1/3 cold to 1/3 Hot is pretty regular, and not sporadic) The only thing sporadic right now is when it overheats -it did it when it was cold, and acted perfect when it was 65/70 degrees outside.

Again, thanks. I"ll post back after I do your checks whenever the overheating happens next.

Longhorn2806

All,

my apologies for not replying sooner.

The problem ended up being the head gaskets. There was a small leak, therefore exhaust was getting into the coolant and creating an air pocket where the temperature sensor is (at the very top of the engine). Therefore my temperature reading was pinged at "H", the engine was actually not overheating (no smoke, etc). However, I don't think coolant was getting into the engine because I never saw white smoke out the tailpipe and the car never "shook" like it was going to fall apart

The gasket issue was so small that during a warm day, the issue wouldn't present itself, but on a cold day it would. Little strange to me since the engine would heat up to the same temperature regardless, but apparently the outside temp was affecting the engine in someway to make the issue only appear when it was cold.

The heater core and fan were fine.

If you have any questions, feel free to post back, and I will do my best to answer. Thank you all for your input along the way.

Hopefully this answer helps others who might have the same issue / see the same problem.

Daehawk

My guess is a small head gasket leak....DOH :P