I have a 97 dodge neon that overheats when the a/c is on, I have replaced the radiator cap, flushed the radiator, changed the water pump, the fan relay switch, and thermostat. What do u think is the problem if all that didnt fix it? Or maybe what what next step should be?

 

Check over your radiator for any damaged fins or anything physically. I took mine out and flushed it out and found that about 50% of my fins just fell right out of it when I was rinsing off the front.. They are copper cores and rot out and deteriorate like any other part on a car. Another thing, check to see if your fans are running when you have your A/C on. They should be running the whole time your A/C is on. If not, check your relays again.

 

Could it be the coolant sensor ?

 

Usually if its the coolant sensor, you get lower readings, I beleive..

Physically take out your radiator and check over it, make sure the fins are secure in there. I just had to replace mine being the fins fell through when I pushed on them.. thats not supposed to happen, haha

 

fins ? you mean the things i can see by looking through the bumper ? if so they are all messed up filled with bugs and bent up!! so thats the culprit huh, my radiator ?

 

sounds like it....i need to replace mine this weekend...all the fins in the bottom left corner were just gone....about a 7inch by 8inch section is gone....
my wifes neon overheats when the a/c is on too...so a radiator for that is on the list soon too

you could also remove the fan/fans...loosen the horizontal bolts ontop or the radiator...then pull up the fans and disconnect the wire connectors....once the fans are outta the way you will clearly see if thats the problem

 

Could very well be. Make sure your not looking at the one for the A/C, I think its the condenser there? I would drain out the antifreeze, pull the radiator and throughly look over it. I got a new one off Ebay for about 70 bucks, works fine.

 

thanks, i will check it out tomorrow

 

Yea the one you see from the front is the condensor, you want the one behind it.

 

when you run the a/c, it takes the heat from the inside and leaves it right in front of your rad (the condense core). if your "fins" are jacked you can get a "fin comb" at the parts store to put them right. or you can use a kitchen butter knife (takes longer but better results). your eng rad is more critical wich is why it's behinde the condensor core. good luck.