What causes window fogging?
Thread Starter
Driver School Candidate
Joined: Apr 2011
Posts: 49
Likes: 0
From: Nevada
Thx everyone. I will sell this car before I consider replacing the heater core. I have no interest in either doing that job or paying someone to do that job. My window fogging is honestly very minimal and I am starting to wonder if it is related to coolant loss or not. I can't smell coolant and the "fogging" is pretty minimal honestly. Time will tell; I have a jug of coolant in the trunk just in case. Fortunately this is car#4 and is somewhat disposable if need be.
If you leave the car in the sun the vinyl will emmit a gas that fogs the windows. Especially if the vinyl is cracked or worn out on the dash. The film on the window is very difficult to clean off. Put some good vinyl conditioner on the dash with UV protection and it may help. Put a sun shade on your winshield when you are parked in the sun. If the dash is really bad put one of those carpet for the dash of the car that are custom fit that you can buy almost anywhere.
As a follow up. I always garage the car but I was doing work on the garage last week and I had to park it outside and I had the film on the windshield because of it being in the sun and my dash is in perfect condition. Same thing happens with my Toyota Avalon
Thread Starter
Driver School Candidate
Joined: Apr 2011
Posts: 49
Likes: 0
From: Nevada
good info. thx guys. i drove the car yesterday about 100 miles on freeway, temp held great. but right at the end, i did some very slow 10 mph driving for about 10 min and temp almost hit the red. once i got rolling at speed again, temp came down. got home, looked in coolant reservoir and it was empty! so i figured i must have a leak. but aa the engine cooled down, coolant refilled the reservoir all the way back up to the lower mark where i filled it 3 days ago. Later, i ran the car at idle in the driveway for 30 min and temp stayed right in the middle. ran heater while idling in driveway and it is working fine. Now i am suspecting hydraulic clutch fan. Fan appears to turning all the time (as well as the 2 electric fans on front), but could the hydraulic fan clutch be faulty, causing the fan to not be turning fast enough?
Pole Position
Joined: Dec 2009
Posts: 3,278
Likes: 317
From: ct
Sounds like you need more coolant and you have air in the system. The resevoir should never be empty. If it's empty then you're just sucking air into the system, which you should bleed out. Air effects how the gauge reads. When I (and many, many other members) had air in the system the gauge would go to hot just like yours does even though the engine doesn't overheat. Try bleeding it. Run the engine (with enough coolant) to normal temp, loosen the 17mm bolt on top of the thermostat housing very slightly, and watch the air bubbles come out. When the engine cools down add coolant.
Pole Position
Joined: Dec 2009
Posts: 3,278
Likes: 317
From: ct
If you can take it all the way off and watch the coolant flow freely then you don't have enough coolant in there and you are letting air in.
Whenever I know I'm low on coolant I usually put it in the resevoir first thing in the morning before I start the car.
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Actually if you read the instructions on the coolant recovery tank it says to first fill with coolant from the air bleed screw and then the fill the recovery tank. Then you can bleed the air per above instructions. Also make sure your recovery tank cap is in good condition. If you suspect it isn't change it its only about 4 bucks at your local auto parts store.
Thread Starter
Driver School Candidate
Joined: Apr 2011
Posts: 49
Likes: 0
From: Nevada
OK, so I did exactly as you guys suggested above. Filled the reservoir up, started the car, cracked the bolt, let it run for about 3-4 minutes and then closed the bolt. It never did like many air bubbles were coming out- it came out a pretty decent stream of fluid. Let it sit and idle in the driveway and it did OK, but temp was a little above midrange. It is hot outside, prob 105 degrees. Then I drove around the neighborhood slowly and within 5 minutes the temp was rising gradually. Pulled back into the driveway, chevked the reservoir, and it was pretty close to full still. Let it idle for about 2 minutes to try to get it to cool down a bit, but it was just below the red line. Shut it off, and within 60 seconds the fluid boiled out the reservoir overflow tube and onto the ground. So it is clearly not a sensor/air problem; it is really overheating. I guess I will replace the fan clutch and see if it helps. How do you test your radiator to see if it is partially clogged?
Thread Starter
Driver School Candidate
Joined: Apr 2011
Posts: 49
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From: Nevada
One other idea: what if I have one or both of my catalytic converters clogged? would this cause the engine to run overly hot and overwhelm the cooling system's capacity to cool the engine in the southern nevada summer heat? I just thought of this because my engine still has an occasional misfire after it gets warmed up, but not when the engine is cool (I have a long previous post about this issue). Would I be able to diagnose a clogged cat by jacking the car up, letting it run until it is warmed up, and then looking underneath to see if the exhaust manifold on either side is red hot?
Thread Starter
Driver School Candidate
Joined: Apr 2011
Posts: 49
Likes: 0
From: Nevada
OK. I got the car warmed up to midrange by letting it idle for awhile and checked the cats; they look totally normal. So I refilled with coolant again and 3 hours later went for a drive. By this time a storm had blown through and ambient temp is now down to 81 degrees. The car WILL NOT overheat at this ambient temp. I tried a whole bunch of stop and go driving, slow speed in 1st gear, stuff that would have made it overheat rapidly in 105 degree ambient temps. I am really surprised that a 25 degree ambient temp change makes this much difference. What is the deal? I am starting to doubt that the source of the problem is a faulty fan clutch; I could hear it cycling on earlier this afternoon when I had the car idling in the driveway as it heated up to temp...