Sportage with Overheating issues

Good Morning,
My daughter purchased a 1998 Kia Sportage and has driven it for about 80K now. About the time summer hit...we started seeing a heating issue whenever she turned on the AC. The interesting part is.... if she gets on the freeway...it continues to get hotter. I have replaced or had replaced the thermostat, fan clutch assembly, belts, hoses, as well as had the radiator and engine power flushed. The technician said I have no head leaks and such since everything holds pressure properly. I have not replaced the water pump since the technician said the water is being circulated properly.

I noticed last evening that when you are driving and you have the AC on... and increase the speed of the fan, the temp gauge takes a step upward almost like an electrical or grounding issue somewhere.

Any suggestions other than taking this reconfigured Korean beer can out back and burying it will be appreciated!

Thanks,
DocZachary

i dunno what causes it but the only thing i can think of is a clog in radiator and bad water pumpbut these were nixed for the most part. what about the mix of antifreeze?that would affect over heating.any way if you decide to change the water pump. that i read some where that the water pump is a part that usually goes bad 80k-150k miles . and if you get top that part you swhould also change the timing belt as it is a 70K part and is do to fail.

1st: the temperature gauge going up instantly as you turn on the a/c or blower is a common problem due to electrical connection only: some poor grounding contact or insufficient size supply wires cause a change of voltage at the receiving end when you turn on the equipment, such as wipers, blower... . Several have solved this at least in part by running new heavy gauge ground wires all over the place. Bottom line: this is an annoyance but not a problem.

A water pump that does not leak is 99.9% of the times a good pump....otherwise it would mean the impeller has been eroded away, a rare occurrence. THe change of water pump at the time of changing timing belt is just to avoid going back into that part of the engine to change the pump in case it would start leaking thereafter ....the water pump is not external as in most other cars but is hidden inside the timing belt cover...so opening all of that just for the pump is not desirable. So better do all jobs as a preventive maintenance once and for all at same time. As e-powers suggests, the timing belt at 70,000 miles is a dead duck and could leave you stranded in the middle of nowhere at any time and experience by all dictates a change around that mileage. Instructions here: www.geocities.com/lmp4203/kiasport/TimingBelt.zip

Finally, if you have no signs of steam escaping the radiator or of foam building on the inside of the oil fill cap (signs of a blown head gasket), I would not get into heavy dollar expense just to see the needle going down. Try instead to use the heater at full heat and full speed (open windows as necessary to cope with it) to see if that reduces the temperature: the heater core IS a heat dissipating radiator and if it does reduce the engine temperature noticeably, it could indicate a poor heat exchange at the front radiator....a radiator contaminated by corrosion or mineral deposit (using tap water containing mineral salts is a no-no) is NEVER restored by so called radiator cleaners or power flush: it would take acid cleaning and this is done for industrial heat exchangers installations only.

To those of you whom replied...thank you. I have finally solved the problem.... but it has taken replacing most everything to get it fixed. I went to Kia and purchased a new fan clutch and saw the heating issue increase. Called Kia stating they sold me a defective fan clutch and was told they only honor the warrenty if I bring it in and they check it out. I bit the bullet and took it to them. They called me later that day and told me MY MECHANIC put the fan on the fan clutch backwards and it was blowing instead of sucking. I informed him that when you purchase a fan clutch for this car.... it comes as an assembly and whomever builds this thing put the fan on backwards. It concerns me when the service people don't know their own product. So now... I have replaced the belts, hoses, fan clutch, thermostat and sensors. This took me to either the water pump or radiator. Kia wanted to replace the radiator for $750. I told them no and picked up the car. I called around and got a new radiator for $159 and had Pepboys install it for $60 (negotiated down from $120 since they had made so many errors with the repair.) I picked the car up last night and drove it all over hell and back. The needle never rose above the middle line.....so I hereby declare it fixed.

As far as the suggestion of boiling out the radiation (thanks for that) you have a hard time doing that when the radiator is a hybrid plastic top and bottom with a metal center. All the houses who boil out radiators told me they wouldn't touch it.

But it is fixed.... thank you for your replies and I hope to be able to add something useful in the future.

Best Regards,
DocZachary

They called me later that day and told me MY MECHANIC put the fan on the fan clutch backwards and it was blowing instead of sucking.
... I hope to be able to add something useful in the future.

Well... this is a very common confusion....look closely.. and when you install a fan "backwards" , it will in fact move the air in the same direction. Look at the position of the blades..and they are at the same angle..., forward..or backwards:to make a fan reverse direction, is MUST rotate in the opposite direction, or you must twist the blades 90 degrees. WHen you install a fan backwards, the "twist" is 180degrees..so back to where it was.
WHile the blades are optimized to be used in one way, because they have a slightly curved shape, they will still pull the air if installed the wrong way, though somewhat less efficiently .
...ANd finding the source of the problem, the radiator in this case, IS "something useful" as an information: it reminds that it does happen...and thanks for posting it.
probably, water would flow very freely through the radiator and there might be no teltale sign of degradation: but a very thin deposit of mineral salt..like when topping a radiator with water from a well, generally containing high doses of minerals, that will scale over the metal with the heat and ruin heat exchange dramatically: Some will take bottled water to top the radiator claiming that tap water must be avoided: some bottled water contain more than 250 ppm of minerals...some labelled as "mineral water", as high as 1000 ppm. A definite NO-NO for radiators.
If one wants to use water, best and least expensive is water taken from a dehumidifier. And other contaminants coming in the radiator by any means, as well as corrosion, will eventually kill a radiator ability to exchange heat.
Problem is....it would be interesting to have some convenient positive means, other than replacing the radiator.. of evaluating the condition of a radiator.

why even worry about the minerals, you can purchase "Pre-mixed" anti freeze with the correct water content at any auto supply store, Prestone makes one as do most of the major manufacturers. Costs a few cents more, but it is ready to pour right out of the jug.

the inside was flushed. what about the outside?