Tech Support banner

Status
Not open for further replies.
1 - 9 of 9 Posts

·
Registered
Joined
·
5 Posts
96 Jeep overheating

this post refers to a previous post, but was split apart. the original thread being referred to is here

I have a 96 jeep and it overheats. I have read all the post on overheating on here so I joined the group to talk about my problem. I basically have the same problem with one difference. When my jeep overheats(goes almost to the red line) I can turn on my defroster to heat and it cools down. Does that make sense and why does it cool down when the heat is on? I have flushed the radiator, added new coolant, and replace the thermostat today because for some reason it went all the way past 260. This time when I tried to turn on the heat to cool it down it was blowing cool air not hot air. So that is when I took it home and did the flushing and new thermostat coolant and ect. Some say it could be the fan is not working yet when it is running I see the fan moving but can not say for sure it is when I am driving. I do not have a radiator leak so thats not the problem. I guess what I am saying is what does the heat being turned on have to do with the radiator cooling off?
 

·
Registered
Joined
·
2,290 Posts
ShielaL,

Sounds like your radiator is clogged and needs to be replaced. They do clog up and at 10 years old this is probably the problem. Solder blooming and corrosion tend to be the main problems. One other problem may be mixing standard antifreeze with the 5 year antifreeze, turns the antifreeze to jelly and just makes and very expensive mess to clean up!!

http://www.radiatorinfo.com/modine.html

Do not waste your money on having a radiator shop "rod" out the original radiator as this may weaken an already old and fragile radiator and it does not cost much more for a completely new unit.

I would probably purchase a mail order replacement and install it yourself or have it installed locally.

Check these links for pricing info. Probably under $150 I would guess?? I have had good luck with Modine products in the past.

http://www.radiatorbarn.com/s3.asp?make=JEEP&year=1996

http://radiatorscom.reachlocal.net/?scid=47446&cid=4398&tc=05082215515217461&kw=704106

There may be other sites to check as well, do a google search and see what you can find.

JamesO
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #3 ·
JamesO said:
ShielaL,

Sounds like your radiator is clogged and needs to be replaced. They do clog up and at 10 years old this is probably the problem. Solder blooming and corrosion tend to be the main problems. One other problem may be mixing standard antifreeze with the 5 year antifreeze, turns the antifreeze to jelly and just makes and very expensive mess to clean up!!

http://www.radiatorinfo.com/modine.html

Do not waste your money on having a radiator shop "rod" out the original radiator as this may weaken an already old and fragile radiator and it does not cost much more for a completely new unit.

I would probably purchase a mail order replacement and install it yourself or have it installed locally.

Check these links for pricing info. Probably under $150 I would guess?? I have had good luck with Modine products in the past.

http://www.radiatorbarn.com/s3.asp?make=JEEP&year=1996

http://radiatorscom.reachlocal.net/?scid=47446&cid=4398&tc=05082215515217461&kw=704106

There may be other sites to check as well, do a google search and see what you can find.

JamesO

My husband did flush out the radiator so I don't know if that is what the problem was or not but I did do a check on the error code this afternoon and this is what it said..........1 2 2 2 5 6. I think the last two numbers are the ones that say what the problem is right? Do you know what these numbers mean? As for replacing the radiator that has crossed my mind as well and the ones I priced are 156 but there is somthing else that comes with it that cost extra which made the price jump to 257. I checked it out at auto zone so I can not remember exactly what it was that made it jump up that high. If you know what the error code means can you please let me know? This is driving me nuts. :4-dontkno
 

·
Premium Member
Joined
·
3,884 Posts
The Jeep is a '96, right? It should be OBDII, and that isn't an OBDII diagnostic trouble code. Take it back to Autozone and have them pull the code and write it down and repost what it is. If the person who pulls the codes for you isn't lazy, they can also you get a printout of what the code means.
 

·
TSF Team Emeritus
Joined
·
5,580 Posts
this sounds like 12, 22, 56 to me.

hold on, and i will try to find the meanings of those exact codes

EDIT: ok, here is what i find...

i guess they are the same as any chrysler....

12, direct power to ecm was disconnected within the last 50 key on cycles. (battery was disconnected or ran dead recently)

22, engine coolant sensor voltage either above or below acceptable range. (coolant temp reading is incorrectly reported to ecm by sensor)

and i think that last one you are seeing is a 55, which simply means, "end of report" since chrysler doesn't list a 56, and it's hard to read a flashing light.

based on this, i think either that sensor is bad, or the water/antifreeze in the engine is so low it isn't touching the sensor. you might also see if the wire connector has fallen off the sensor.

you will find this sensor on the top of the engine, near the large hose coming from the radiator. it looks a little like a spark plug, with a wire or two running to it. make sure this plug is connected.

also make sure the coolant level is high enough.

to answer your original question,
SheliaL said:
When my jeep overheats(goes almost to the red line) I can turn on my defroster to heat and it cools down. Does that make sense and why does it cool down when the heat is on?
the heater has inside it a small radiator, when you turn the heater on, water is diverted to it, and as it heats the inside of the car, the water is cooled down. so in turn, using the heater will make the cooling system more efficient.

what bothers me, is that usually the heater only blows cold air like you report if the engine doesn't have enough water in it to push water through the heater core.

at first it sounded to me like your thermostat was stuck, which would cause it to not use the radiator, explaining why it would heat up. the heater takes it's water through a diverter that doesn't have to go through the thermostat, so a stuck thermostat will still allow water to the heater.

but, you have changed the thermostat, and so we now know it isn't stuck...




also, i am moving your posts into their own thread. more than one question per thread gets confusing.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #6 ·
WaltSide said:
this sounds like 12, 22, 56 to me.

hold on, and i will try to find the meanings of those exact codes

EDIT: ok, here is what i find...

i guess they are the same as any chrysler....

12, direct power to ecm was disconnected within the last 50 key on cycles. (battery was disconnected or ran dead recently)

yes that makes sense the battery was changed last week. It was dead as dead can be

22, engine coolant sensor voltage either above or below acceptable range. (coolant temp reading is incorrectly reported to ecm by sensor)

yes again that makes sense as it overheated Sunday making overflow bottle completly fill up.

and i think that last one you are seeing is a 55, which simply means, "end of report" since chrysler doesn't list a 56, and it's hard to read a flashing light.

I thought it was a wrong code as well so I did it again after 35 minutes and it flashed the same code 12 22 56. I thought the 56 sounded odd too.

based on this, i think either that sensor is bad, or the water/antifreeze in the engine is so low it isn't touching the sensor. you might also see if the wire connector has fallen off the sensor.

its possible the sensor could be bad because I know there is plenty of antifreeze in there as we just flushed the radiator and refilled it. So maby it is giving the readings from when all the trouble started Sunday.

you will find this sensor on the top of the engine, near the large hose coming from the radiator. it looks a little like a spark plug, with a wire or two running to it. make sure this plug is connected.

also make sure the coolant level is high enough.

to answer your original question, the heater has inside it a small radiator, when you turn the heater on, water is diverted to it, and as it heats the inside of the car, the water is cooled down. so in turn, using the heater will make the cooling system more efficient.

what bothers me, is that usually the heater only blows cold air like you report if the engine doesn't have enough water in it to push water through the heater core.
the only time it has blowed cold air was sunday when all the trouble started. When I got the jeep home it was extremely hot. The overflow was completley full. So I am guessing that is why the water was not pushed through the heater core.

at first it sounded to me like your thermostat was stuck, which would cause it to not use the radiator, explaining why it would heat up. the heater takes it's water through a diverter that doesn't have to go through the thermostat, so a stuck thermostat will still allow water to the heater.

but, you have changed the thermostat, and so we now know it isn't stuck...

yes we have changed it. So now we need to figure out why its overheating. We are taking it in Friday so I will post you all on what was found out. Even what that 56 means! LOL :wink:



also, i am moving your posts into their own thread. more than one question per thread gets confusing.
Thank you I am a newbie and could not figure out how to start my own post. :grin:
 

·
Registered
Joined
·
2,290 Posts
Air pocket in cooling system??

I do not know this vehicle, so there may be a procedure for removing air from the cooling system??

JamesO
 

·
Registered
Joined
·
57 Posts
Air pocket in system

James O is probably correct in saying that you may have an air lock in the system. That is the usual cause of overheating and no heat from the heater after a coolant drain and refill (no matter what caused the drain) I usually start the engine and let it idle with the vents on and the temp at hot, fan on hi.
as the temp guage starts to rise, rapidly press the throttle to about 3-4000 rpm and release it. Repeat blipping the throttle until you either get heat from the vents or it starts to overheat. Fill up the overflow bottle as often as necessary during this proceedure. If it overheats, let it cool down and try again. It sometimes takes a heat soaking time to open the t stat if the air is there. Usually this process will remove the trapped air from any cooling system, including those that have air bleeds (cavaliers!!!) that wont remove all air. I usually leave the rad cap off so the trapped air meets less resistance as it moves thru the system. Btw if your jeep has the two electric cooling fans rather than the mechanical one driven by the serpentine belt, make sure they are operating properly. All vehicles will overheat if the electric fan doesn't work!.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #9 ·
Sounds like your radiator is clogged and needs to be replaced. They do clog up and at 10 years old this is probably the problem


turns out I need a new radiator. That is what the mechanic said. He checked everything out and every thing checked out so that only leaves the radiator. So hubby will attempt this tomorrow. Thanks for all the help guys. :wink:
 
1 - 9 of 9 Posts
Status
Not open for further replies.
Top