Toyota Camry 98 V6 Overheating?

Question

i need a serious help here as i'm suffering a lot with my malfunctioning car. i went to several places and every mechanic is telling me different problems. i'm confused!

my car is a Toyota Camry 98 V6, its getting overheated at higher speed, say beyond 40/50 miles an hour. but its just fine at idle or lower speed. every time i turn on the heater at full, it blew cold air. i did some research and found that the t-stat might be bad. i changed t-stat, flushed the radiator, put new coolant. now my heater blows hot air both at low and high speed. but the problem REMAINS! it still getting overheated at higher speed. i can't drive more than 30 miles an hour, the heat gauge gradually goes to the red mark, then i have to slow down below 20 Miles, then it goes back to the normal, then again i speed up again it goes to the red mark and on and on and on .... i'm tired of driving with my hazard lights on.


i took my car to a mechanic yesterday, he said he tested the system, everything working fine. he checked water pump, its working fine (idk if he really checked). he suggested me to change the radiator which 'might' solve the problem but he's not sure.


any help with this regard will highly appreciated!

Answer 1

#1. Have an inexpensive *cooling system pressure test done to see if you have any external or internal compression pressure leaks.



#2. Too bad you didn't drain, flush and CLEAN your 15 year old cooling system with one part powered acid cooling system cleaner to get the rust and corrosion out.

Answer 2

Here is my thought - and only because I had a similar situtation on an 89 Jeep Wrangler once.



Temperature sending unit or dash gauge failing -

The only real way to test this is to put a digital thermometer next to the hot side of the radiator hose and check the actual temperature at speed and idle. You can buy digital thermometer (usually with volt/ohm gauge) them pretty cheaply now ($20-40 range) - and you may be able to secure the heat sensing probe just between the radiator hose the the radiator hose nipple so you get a good metal contact.



Then snake the wires into the cabin and compare the actual temp from the meter to the temp gauge in your car and see if the coincide. You should be running at thermostat temps all of the time.



My Jeep had an analog gauge that would go up to 240-260 driving highway speeds on hot days but the digital temp never went beyond about 210 F and quickly went back to thermostat temps after idling for a few minutes (195).



I ohm'd the sending unit and it was fine and replaced it even and it still didint' fix the problem then I replace the circuit film (board) that controlled the gauges and the temp gauge itself and it still didn't fix the problem - never figured it out but I knew it didn't overheat and never had any problems well over 100k miles.

Answer 3

Three things , do the cooling fans run when the engine runs hot , the impeller could be slipping on the water pump , or the head gaskets are leaking due to over heating the engine .

Take off the oil fill cap and if there is a cream colored substance then the head gaskets are blown .

Answer 4

I can't believe the non answers that are posted. The answer come from people who have no knowledge of a cooling systen and cause great expense and time wasting following the info. given.

You must remember RADIATORS cause overheating problems.

Go now to a RADIATOR SHOP and have your radiator cleaned.

Flushing is a total waste of money. You can do nothing to fix the problem as the radiator must be removed to be cleaned. This is your only solution so stop wasting money and get going.

Answer 5

You must us ONLY GENUINE TOYOTA RED coolant in this engine and NO PRESTONE, which is a LIAR company! NOBODY uses it in ANY FACTORY anywhere! Perhaps you just have a collection of DEBRIS in the space between the RADIATOR and the A/C condenser! This is VERY common on OLDER CARS! THIS SPACE attracts SEEDLINGS, LEAVES< PAPER, FUZZ< INSECT BODIES< and they ALL interfere with proper AIR FLOW! Take a can of GUNK ORANGE ORIGINAL engine cleaner to ANY DIY car wash and SPRAY EVERYTHING CLEAN! Bring a SCREWDRIVER to acces this RAD-CONDENSER sandwich space and POWER WASH IT (low pressure ONLY) BAD HEAD GASKETS will show up as COOLANT in oil; OIL in COOLANT! BUBBLES in RAD HOSES and GURGLES inside th car when engine is WARMING UP or COOLLING DOWN! IF ENGINE EVER OVERHEATED< then it may require NEW HEAD BOLTS ONLY! They will STRETCH and can cause ENGINE LEAKS! They are PROTECTING the BLOCK and HEADS from warping this way and SACRIFICE themselves! If you STILL have problems, GET TOYOTA TO DO A FULL COOLING SYSTEM FLUSH and use their FACTORY RED COOLANT ONLY! NO prestone may be used here. and replace the COOLING FAN SWITCH as a matter of AGE and MILEAGE using genuine TOYOTA PARTS ONLY! GOOD LUCK!!

Answer 6

Maybe the temperature sensor is bad. Are there any symptoms that the car is actually overheating besides the guage saying it is? Like is there steam coming from the overflow? I dont know what else It could be. That is odd.

Answer 7

I know it sounds weird, but check your battery connections, ensure they are tight and clean, a bad connection can give a bad temp reading. It will cost you nothing except 2 minutes of your time, If it is the problem it will be the cheapest fix you are ever going to have.

Answer 8

I had a Ford Contour. It was not a very reliable car. The motor is not in the wrong place, but I don't think it is built very well. Take a look at a used Mazda Protege. They are small, inexpensive, and very well made & reliable. Good Luck.