Hi all. I am trying to help my sister in law with her Neon. It is a 1996 SOHC 2.0 Neon with well over 100k on it. ran fine up until last week when it started overheating. It seems to only overheat in gear. Idles fine, temp guage stays in the middle where it typically lies. As soon as you put it in gear and drive it moves fairly quickly up the guage and pegs out. I am stumped and after a search of the internet came up dry, I figured I'd ask the best site on the net for help.


Thanks alot

 

Coolant level good? Thermostat opening fine?

RP
Zach

 

Both seem to be good. The coolant is beyond nasty however. Could it be a clogged radiator?

 

Nasty coolant can clog up the radiator core and passages in the engine and the heater core too. The thermostat may also be stuck. Nasty coolant usually means that maintenance has been poor so the cooling system and even the oil are places to look at.

If and when you clean the system out, you may discover that the thermostat is dead, and you might create leaks that the dirt was plugging, so don't be surprised. My experience is that about 30-50% of the time when I do a chemical flush of the cooling system, I kill the t stat and have to replace it. So I just routinely replace them now.

The radiator core may need to be "rodded out" to remove deposits that are stuck to the cooling passages.

There is also a possibility that the main radiator hoses are collapsing due to rusting away of the steel internal hose reinforcement springs. You can usually spot this by squeezing hoses to see if they are soft or watching the hoses as you rev the engine once it is hot. As the RPMs rise the hose will collapse and of course your coolant temp goes up. New hoses usually fix that problem.

Good Luck,

Jim Henderson

 

How dose it drive....


I heard this story from someone else, where the transmission cooler was actually inside the radiator. Once that started to leak, the trannsfluid and coolant mixed. What i heard happend was the transmission then blew out. Which doesnt seem the case with you.

But however, different trans and engines act different ways, so this may not happen with your car. My guess is though, if you do distinctly tell a corrolation between the temp guage, and weather or not it is in gear.

You also said the coolant is very bad, which also supports my though.

Drain the coolant, and replace it. It dirty anyway, maybe that alone is what is cuasing the temp rise.
If you notice that the coolant it becoming dirty again within the week or month you put it in, your most likley leaking trans fliud in the radiator. Also check your transfluid level.


Another though i had, perhaps there is somthing wrong with a sensor or somthing.
And it is automatic which dose effect how to motor runs to a piont sence that trans is linked to tyhe motors ecu, so once you put it in gear the engine may start to run lean. Cuaseing the heat build up. But if that occurs, your check engine light will be on.
good luck isolating the problem

 

do the cooling fans come on when it gets really hot it could just be a faulty relayor when the a/c is turned on(if equiped) also preasure test the cooling system to see if there are any leaks check carefully around the head gasket those noen 2.0 and 2.4 are known for head gaskets

 

I would say it can be your radiator being clogged, sence it dose seem to only overheat when your driving when the motor needs more cooling.

Im going to find out if that radiator on your neon is the type that cools the transfluid as well. If it isnt we can eliminate that problem.

 

I've got a 98' neon, with 180,000 on the ticker. Never has it overheat, but I've changed the coolant at least four times since I've owned it. If you don't maintain the cooling system , you're going to get burned. How long do you think that thermostat is going to last. I don't want to hear if it ain't broke ,don't fix it. That's all bull... You change your oil at different times, get off your *** and change the coolant....and the thermostat...

 

Try going to this site. They are pretty sharp on their Mopars from my experience anyway.
http://www.allpar.com/forums/index.php?showforum=17

I would agree that a good flush and thermostat would be a good place to start. Check the tranny fluid to see if it has signs of coolant in it. Also a new radiator cap. Have you pulled the plugs to see if any of them show signs of coolant? Dodge has a different HG that fixes the original problem and they can tell you how to identify it without pulling the head.