Overheating, no heat, smell coolant, lots of steam. Kia Sedona.

jenniferlmjenniferlm Member Posts: 14
edited December 2018 in Kia
Drove van to work twice and smelled slight coolant smell. Kept an eye on temp and ran normally. (9 mile drive). Drove van back home and coolant smell was a little stronger and saw some steam coming out from under the hood, not a lot, and temp was still normal. Went to go to the store 2 hours later and went .6 miles and stopped at red light and noticed van started running warmer than normal (just barely above 1/2 way mark). Took off and it stayed at this temp for about 3 miles, then went up to 3/4 on the temp. Made it to store, checked reserve tank and was normal. Went in store for over an hour. Started up van to go home and the temp went back up after leaving the parking lot. Then, I noticed there was no heat blowing from the vent....just cold air. The temp then started fluctuating from 3/4 to hot but mostly stayed at 3/4 until about 100 yds from my driveway, where it went all the way hot. When I shut it off, a LOT of steam came out from under the hood but I didn't hear any hissing or popping sounds or anything like that. I know I should have pulled over but it was later at night and out on a back road so there was no way I was stopping. I just need to know if the thermostat is stuck or the water pump went out or what. My husband will look at it when he gets home from work, but I'd like to give him some direction on where to look first. Any help would be greatly appreciated!!


  • ray80ray80 Member Posts: 1,655
    edited October 2014
    Smelly steam from engime compartment makes me think about leak somewhere. 10 YO vehicle, may be a hose that has seen better days. Of course it may be something entirely different also :)
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,482
    I think Ray80 is on it---either there is a definite leak in a hose or fitting or the radiator, or you are overheating because a) cooling fans aren't working b) radiator is clogged c) head gasket issues.

    Usually, a slow overheat such as you describe is attributable to loss of coolant from a leak or gradual heating up of the coolant because the cooling fans aren't working.

    Things like a stuck thermostat or bad head gasket usually result in a very fast overheat and you probably wouldn't have gotten very far with those defects in place.

    for you to smell coolant means that it is exiting the system somehow--either from an actual leak, out of the coolant reservoir, or worst case, out the tailpipe from a bad head gasket.

    Whatever the case, you must not drive this car in this condition for very long.
  • jenniferlmjenniferlm Member Posts: 14
    The steam was coming out from under the hood in general and when I last cut it off and a LOT of steam came out, it seemed to mostly come from the driver's side of the hood
  • jenniferlmjenniferlm Member Posts: 14
    Do you think it would be okay for me to start it and let it run long enough to see where it may be leaking? I'm really afraid to after the amount of steam it let off when I cut it off last night
  • ray80ray80 Member Posts: 1,655
    First thing I would do is open the hood and look for visible signs of leak (wet spots). Then check coolant level at radiator ( if it has cap that allows access) and/or overflow bottle and ensure there is adequate coolant. Then start and run at idle speed until it heats up enough to do whatevere its going to do. I would tend to not drive it ( As Mr shifty stated)
  • jenniferlmjenniferlm Member Posts: 14
    We'll try it here in a little while. I'll keep you posted! Thanks so much.....be back in a couple hours!
  • jenniferlmjenniferlm Member Posts: 14
    Okay, so we found about an inch long split in the hose that is under the breather (not the one that runs to the reservoir tank). We replaced it and I let it idle for about 5 minutes while we added coolant to the reservoir and to the actual radiator (reserve was empty but radiator seemed to hold very little coolant), then I drove it about 2 miles and noticed the temp was going up but I had no heat. I turned around to come home and about 1/4 mile to go it ran completely hot. I got home and turned it off and you could hear the water boiling in the radiator. I am wondering if perhaps the thermostat is stuck shut and the pressure built up and split the hose? I'm just not sure. Anyway, it's parked until Sunday until we can get to work on it again. Any and all input is greatly appreciated. Oh, and by the way....my husband did try to take the radiator cap off when I got home and yup, it blew the cap off and spewed some coolant all over. Not a lot, but enough to scare the crap out of him and for me to say "I told you so....." :)
  • ray80ray80 Member Posts: 1,655
    Hhmm, Well just filling the radiator doesn't always fill the cooling system. Better ti fill it (plus the overflow jug) and run it with radiator cap off and add coolant as needed when it warms up. If it just starts boiling THEN it is likely stuck closed T-stat that didn't set a code/light. Depending how this particular cooling system is made , after the cap goes back on there may (or may not) be bleed screw(s) to get air out of system (which is done with vehicle on level ground and heat on full)
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,482
    No heat means no circulation of hot coolant---either due to lack of coolant, air blockage in the system, or a stuck thermostat.

    If someone is brave enough, they can feel the entrance and exit hoses to the heater at the firewall, from inside the engine bay. If both hoses are warm after the car's temp gauge comes off COLD, the thermostat isn't stuck.
  • jenniferlmjenniferlm Member Posts: 14
    Okay, so we had a stuck thermostat. He replaced it today and now it won't start. It cranks fine but just won't turn over. It kinda sounds like it isn't getting any gas. Is there a possibility that he knocked something loose while working in that area? Or is it possible that he didn't get a good seal on it? He put in a new o ring with the new thermostat.
  • jenniferlmjenniferlm Member Posts: 14
    By the way.....you guys are AWESOME!!
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,482
    Well hard to say---but it did run after the overheating incident, or haven't you tried it since overheating? I'm a little concerned about overheat damage here.
  • jenniferlmjenniferlm Member Posts: 14
    The last time it overheated (after replacing the hose) I just cut it off when I got home and haven't tried to start it since. I was afraid to cause damage. It only ran all the way hot for about 1/4 mile, but I know that could be enough to do damage. When I cut it off, there was no steam, no weird noises...just normal cut off.
  • jenniferlmjenniferlm Member Posts: 14
    Okay, so we found out why it wouldn't start.......something had been unplugged and we plugged it back in and it started right up. HOWEVER....It ran a little rough while idling in gear. Then when I drove it, the engine seemed to vibrate or shimmy when I accelerated and the check engine light came on when I accelerated and went off when I let off the gas. And, once again, no heat came out and it overheated after driving about 1.25 miles. Some more information: when my husband had the engine shroud off, he hosed down the engine and everything under the hood with water from the garden hose. I don't know if this has anything to do with anything, but I'm sure it doesn't have anything to do with it still overheating. It is also still blowing cold air, no heat. I had spinal fusion surgery and have been out of work for 6 months, so i have no money to take this to a mechanic. (We are doing good to keep all the bills paid on one income) so ANY help you can give would be very, very helpful and appreciated.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,482
    Okay---can you fill up the radiator, start the engine and leave the cap off to see if there is a) any circulation in the coolant--a flow and/or b) any excessive air bubbles, like a fizzy ? BE SURE to stand clear of the top of the radiator as much as possible and wear eye protection goggles.

    One good test for a bad head gasket (certainly plausible given the serious overheat) is to pressurize the cooling system with a pump you can buy at Autozone for $15 bucks---then, while leaving the system pressurized (2 or 3 lbs over the radiator cap rating), extract the spark plugs one by one--if you see coolant on any one of the plugs, then the head gasket is definitely toast, and/or the cylinder head might be warped.

    You can also test the coolant chemically for combustion gases by buying a simple test kit--so that might be easier.

    You might also borrow a scan tool if you can to find out what the check engine light is all about.
  • jenniferlmjenniferlm Member Posts: 14
    Don't see any fizzy bubbles in the radiator and I checked the oil and it looks normal, no milky appearance. Nothing coming out of the tailpipe. I'm beginning to wonder if there's a blockage somewhere in the radiator or something. We're letting it "dry out" after he hosed everything down and see if that helps any as far as how badly it's running. I'll keep you posted.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,482
    Overheating can be a complex problem, so don't feel discouraged. Yes, a blockage in the radiator can cause overheating, but I am concerned because of the RAPID overheat.

    Did you notice any circulation in the radiator--it should be swirling around in there with the motor running.
  • jenniferlmjenniferlm Member Posts: 14
    I'll have to check, but I do know the fan is running, so that's not it. do you think that it's running so rough because he sprayed down the engine and got some components wet or something? I can't drive it far enough to get it somewhere to hook it up and see what code it's throwing. :(
  • ray80ray80 Member Posts: 1,655

    do you think that it's running so rough because he sprayed down the engine and got some components wet or something? I can't drive it far enough to get it somewhere to hook it up and see what code it's throwing. :(

    Could very well be, there are some electronic components under the hood that might not like getting wet,even spark plug wires if old enough wouldn't like it.
  • jenniferlmjenniferlm Member Posts: 14
    Okay.....so we tried another thermostat just in case. While it was running, I happened to look over at the reserve coolant tank and notice it was "boiling". I went over and took off the top and pulled out the little hose attached to the top and it quit boiling. Apparently, there is air coming out of this little feed hose into the reserve tank. What the heck? The guy at the parts store said that means I have a blown head gasket.
  • jenniferlmjenniferlm Member Posts: 14
    Oh, but the good news is that the water must have been why it was running so rough....it's running fine now (except for the overheating and having no heat)
  • BigMike_773BigMike_773 Member Posts: 2
    Jennifer did you ever find the problem. My car is doing the same exact thing

  • BigMike_773BigMike_773 Member Posts: 2
    You have air pockets in your cooling system. You must bleed the system. 
    Step 1. Locate bleed strews.  Look near thermostat or upper coolet housing. Some cars have two. 
    Step 2. With a 3/8 or often 8mm loosen the bleed strew without removing it. 
    Step 3. When car is cold, open radiator cap and pour in Antifreeze until you see Antifreeze come out the bleed strew location. You may hear air start to escape the bleed strew. This will be a big indication you had air pockets in the system. 
    Step 4. Once you see Antifreeze come out the bleed strew, you can tighten the bleed strew back down. Fill the radiator all the way to the top. 
    Step 5. Turn the cab heat and fan on blast. 
    Step 6. Start the car, with radiator cap off. You may want to buy a spill over funnel to catch the extra Antifreeze. If not just let it spill out who cares. 
    7. Run the vehicle for 20 + until it reaches proper operating temps which is 220 degree fahrenheit. This will kick on the radiator fans. Then you are done. Replace radiator cap. Complete.

    If you look closely you will see air bubbles coming out the radiator or reservoir. The heat should start coming back doing this process. 

    If this doesn't work. 
    1. Stuck thermostat "highly unlikely" but possible. Fill the upper and lower radiator hose with car at operatoring temperature. These are you entry and return hoses. Both should be about the same temperature. If one is colder the the other change thermostats. 
    2.  Blown head gasket. Water in old "milky oil". Back fires. Trouble starting. Mis fires. Lost of power. Some of these symptoms occur when you have a bad coil also.
    3. Temperature sensor makes your car thinks it's overheating but it's not
    4. Lastly and rarest, bad cluster. 

    Good luck people 
    Hope this helps. 


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