92 lexus es300 problem - Toyota Nation Forum : Toyota Car and Truck Forums

pearlwhite92ES · 09-16-2008, 03:56 PM

I've checked all around the lexus site and have found very few answers
to the problem I'm having. My windshield is fogging up and I'm getting a
light coat of oil on the windshield that's hard to clean off. I've checked for signs of the heater core leaking and found no signs of leaking, and even went as far as having the r12 sucked out..The fogging is better now but still fogs the windshields after a period of time.

Does anyone know what this might be? I think I've narrowed it down to a tiny hole in the heater core or the evaporator? thanks for any ideas

frenum49 · 09-16-2008, 04:00 PM

Classic leaking heater core. You already have this one pegged. Must smell coolant in the cab right?

***new echo owner*** · 09-16-2008, 04:16 PM

Was the A/C system low? A leaking evaporator core or expansion valve would put oil on your windshield.

N.E.O.

BlueFusion6851 · 09-16-2008, 05:48 PM

Yep this definitely sounds like your heater core... get a new one and you'll be all set.

pearlwhite92ES · 09-17-2008, 10:31 AM

I have no smell at all of coolant which was just flushed 500 miles ago..Theres
also no leaking on the carpet. I was told once that it still could be the heater core,but most say it would smell or leak.

As for the A/C...it was @ 1.84 and called for 1.92 or something..So no it
really wasn't low but since I had the system evacuated out it don't fog as bad.

I'm thinking of replacing the heater core first since it's the cheapest fix. Anyone know the best place to get a good cheap replacement>? thanks

***new echo owner*** · 09-17-2008, 10:36 AM

If it is the heater core, you would have experience coolant lost, and it wouldn't have make a difference if you evacuate the A/C system or not. And you would definitely smell the coolant if it is leaking. Replacing the heater is not exactly a simple job.

N.E.O.

pearlwhite92ES · 09-17-2008, 10:50 AM

I know toyota has a recall for the expansion valve but lexus said that my car has been done already. If either was leaking would the system hold a charge for 4 years since it was replaced? this problemis a tough one to figure out for me because both could be costly.

***new echo owner*** · 09-17-2008, 10:58 AM

I would suggest holding out on any repair, if it is the A/C system fogging up concern will slowly disappear since the system is empty. If it is the heater core, it would continue or get worst.

The expansion valve may be good,but the evaporator is still the original one.

N.E.O.