Wondering what could cause this?

I am currently 900 miles from home and have little money. Trying to figure out what potential causes could be so I can determine whether its better to try getting it fixed or junk it.

It has a new (now 30K mile) engine in it. The heater core was replaced when the engine was, about 2 or 3 years ago. Had a garage do it. Since then I changed the oil, and had other work done, but the engine and main components have never had a problem.

A couple days ago it was running about 10 degrees hot on the highway. No biggie but it was clearly off. At idle it skyrocketed to overheat/redline. I immediately shut it off. Two days later I finally had a chance to look at it and saw this immediately. Thoughts?

 

That is a sign that your coolant is contaminated. Could be someone mixing different coolants together or an internal crack on the trans cooler (assuming you have an auto trans). I am leaning more towards an internal crack on the trans cooler though...

 

mixxing of orange anti freeze with green standard antifreeze can cause the fluids to jell and clog. that may give results you see. also level of fluid appears low.

Id drain her, then fill with water and a cooling system flush cleaning chemical, follow instructions, then drain and repeat flush. A prestone flush and fill tee kit is also recommended to help clean it out.
Id also pressure test the system, just in case you have a leak as one must ask where the fluid went.

Since you shut her off before overheating, likely no harm to motor.

Stick with the green regular prestone, do not mix coolant, even if the label says you can, just dont do it.

If leak tight, just keep flushing as needed to get her clean

remember that water and the flush chemical will freeze, which can crack your motor, so dont leave that in there with cold weather. also do not leave the cleaner in there beyond what instructions say, as the cleaner if left in there too long will cause leaks as it is corrosive I know a retard dumb "mechanic" who left the flush chemical in his truck for a month, which then caused his heater core to leak, idiot!

So flush put all that crud, clean it up, test for leaks, if good fill with correct green antifreeze.


from now on keep a close eye on the overflow bottle
good luck!

 

Yeah, that looks like the spooge from mixing dexcool with regular antifreeze. If the trans cooler in the radiator failed, you would likely have coolant in the trans too since the coolant is at a higher pressure than the trans fluid in the cooler.

 

I agree with others, looks like mixed coolants. Have you ever mixed coolants, either you or a service tech?

That needs to be flushed, many, many times. Even if you are using non distilled water to flush it, its ok.

Do not be surprised if you have to flush it 6 times to get it clean.