Help! 95 vette with defrost problems

[vetter95]

hi new to this site but this looks like the one to be on if you own a vette, i am having a problem with my windows wanting to fog if the outside temp is under 40 degrees F with or without the defrost on, it has the climate control and seems to be working fine just can't seem to defrost the windows front or side. it dosen't fog if it's 55 degrees F or above. any help or suggestions would be great. thanks

 

[TWISTERUP]

Possible Heater core

Not to be the bearer of bad news but. If you're getting good air flow from defroster and temp. is hot...possible leaking heater core...that is also accompanied by a slightly oily film on the windshield and a sorta "sweet" smell. Does the AC work the compressor should run automatic in conjunction w/defrost mode and is also a slight help in removing moisture from windshield. IMO from your description though sounds like possible heater core. Not a fun job!

Depending on how big a leak you would also be loosing coolant over time (if it is the heater core)

 

[vetter95]

well i don't smell any anti freeze and there are no wet spots on the carpet area, the car has only 47k miles and the windows defog as soon as you turn the car off with no oily film, could the climate control temp sensor be bad, the air seems to not work if the outside temp is below 40 degrees F

 

[TWISTERUP]

Is the engine temperature normal----does the defroster vent temperature feel hot and does the blower fan continue to work when this occurs ?

 

[TWISTERUP]

Ooops

One more question ...when you have the AC on and you push the Recirc buuton , do you hear a very slight change in fan speed ...should sound like it blows a bit harder but not much. I ask this because in the defrost mode it should "automatically" be drawing in outside air...if the recirc door is stuck for whatever reason in the "recirc position" ie heating only the air inside the car in cold ambient temps that can also cause your problem. I say this and I'm not even sure you have automatic climate control or a manual system...my bad.

The test or check will be push recirc button and listen for a slight air flow increase wait 5-10 seconds push the outside air button ...wait... you should here a slight decrease in air flow volume/speed. If you do not here the air volume/speed change when pushing back and forth between the recirc and outside air buttons ...the recirc door may be stuck closed...if that is the problem ,it is usually the worst when the humidity is high.

 

[vetter95]

95 defrost

Twisterup thanks for your time, the defrost is warm and the engine is operating temp and the blower motor works its the automatic climate control option, i will try the recirculate in the morning and see if it works like you said, trial and error i guess thanks again

 

[Rabbit]

Twisterup thanks for your time, the defrost is warm and the engine is operating temp and the blower motor works its the automatic climate control option, i will try the recirculate in the morning and see if it works like you said, trial and error i guess thanks again

Can you control the fans speed?

Does it get up to #10?

 

[vetter95]

yes the fan speed will go to 10

 

[gmjunkie]

Make sure that the drain in the AC housing is clean and allowing the condensation to drain out!! The AC runs with defroster to remove the moisture from the cockpit,if it ain't draining it will fog the windows in a Heartbeat!!

 

[vetter95]

hey thanks for the info, can you tell me where that is located? like at the bottom of the housing or somewhere else? thanks

 

[gmjunkie]

hey thanks for the info, can you tell me where that is located? like at the bottom of the housing or somewhere else? thanks

You'll have to get under the car!!Look up between the rt frame rail and the engine,you should see a small hole or hose on the bottom of the AC evaporator case!

 

[vetter95]

Thanks I will try that this evening.

 

[Rabbit]

Thanks I will try that this evening.

This is just a guess, but remove the pass/side fuel rail cover & inspect the vacumn fittings. Long shot, but worth a look.
:confused