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Overheating 03 neon

I have a 2003 dodge neon, a couple days ago i hit a bump and bottomed out on the front bumper and pulled a transmission hoes. after repairing that my car is now over heating, i have replaces the thermostat and the upper radiator hose. i am not leaking coolant, i have talked to several people on this and they say that it is either my water pump or i have a vapor/air lock inside the block, when i was replacing the thermostat i noticed that my coolant was a milky tanish color and was “chunky” and that is what is making people say that it is an air lock. but my hear is not blowing hot air, that makes me believe that it is the water pump… when i start the car it take the usual 10 or so minutes to reach normal temperature just like it did before all this, but then it shoots up to almost over heating in less than 5 or so minutes… I am really stumped by this and i am a college student so i rally cannot afforded a mechanic unless absolutely nessicary


“after repairing that”

Do you mean you replaced the transmission cooler hose?

ASFAIK, the transmission cooler is actually part of the radiator

Perhaps the coolant and trans fluid are now mixing, inside the radiator

yes after the transmission cooler hose.
Could it be a problem inside the radiator if the hoses are going back into the same places?

I should not do this. You are a college student and this is the way you write?



When you bottomed out, it’s possible you damaged the trans cooler, which is inside the radiator.

In any case, your coolant is clearly contaminated with another fluid

I suggest you also take a close look at that trans fluid. If it’s also strange looking, your problem is most likely the radiator

OP’er may need a new radiator. The coolant line for the transmission fluid probably goes through the inside of the radiator – that’s how it works on my Corolla, unused in my case as I have a manual xmission. Anyway, that line inside the radiator may have cracked, allowing the coolant and transmission fluid to mix. This could quickly damage both the engine and the transmission. Not a good thing. This needs to be addressed asap. If this were my car I’d take it to a local radiator repair shop for diagnosis. They see this kind of thing all the time, know how to test for it, have the tools, and know the repair options available.

I think this is getting beyond what you can accomplish with your skill level and experience. It sounds like you may have a damaged transmission cooler as others have said, or possibly a blown head gasket on the engine, which will cause all of these symptoms as well: brown coolant, overheating, heater not working properly. If you allowed the engine to overheat for long, if you didn’t have a blown head gasket when you started, you may have now. You really need a shop to do a proper diagnosis at this point. At the very least with “brown, chunky coolant” you desperately need a coolant flush. Trapped air will not cause your coolant to look this way–there is something else going on. The longer you drive it like this, the more likely you will seriously damage your car.

Better be checking that ATF as well or you will need a new transmission too.

If you are not getting heat and the engine temp shoots up, you have air in the system and it needs to be bled.

The guy has a much more serious problem than air in the system

He said the "coolant was a milky tanish color and was “chunky” . . . "

I know. I was just letting him know that he had not bled it properly. That way he can do the job right in the future.

Many Neons have head gasket problems, and I fear yours is probably in the same situation. A proper cooling system and engine compression test will quickly determine the extent of the problem. The standard cost here is about $900 to replace a Neon head gasket. You should budget that much at least.

I think they pretty much fixed the problematic head gasket issue by '03, but it sure sounds like that’s what’s going on here.

I think he needs to

  1. test and likely replace the radiator,
  2. flush both the tranny and the engine cooling system, and
  3. pray that no permanent damage has been done due to he fluids mixing.

Antifreeze is very corrosive to engine bearings, I think if the transmission cooler in the radiator is damaged that this car has a short life span.

True, oldtimer, but coolant can’t get to the engine oil via a breech in the radiator. The tranny might be toast, however, but it’s worth changing the radiator and flushing everything out. Often our worst fears don’t turn to reality.

Can’t believe I had brain fade like that-lol.

Good Lord, oldtimer, if brain farts were toxic I would have killed my entire neighborhood by now! Just this past week alone! :slight_smile: