Tonight I used the heater for the first time since buying the car about 4 weeks ago. On my way home tonight from class it was raining so I had my windows up and of course they begin to fog up. So I hit the defrost button and turned it up to 83*. It was still blowing cool air after a while so I turned it up to 90*. Still cool if not colder air. This solved the foggy window problem for about two minutes because then the window starts to fog up again from the cold air. So I shut it off and then had to repeat this cycle probably 6 or 7 times on my way home.

This isn't a huge problem at the moment but in a couple months it will be...plus the drivers side heated seat doesn't work either But that's another issue...

What are some possible causes for this, I have never dealt with the heater or AC before.

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'93 SSE "Guinevere" RIP 1993 - 2019
'01 SSEi "Chloe" Mods: Intense FWI | GenV | WBS Intercooled | 3.2 MPS | 1.9 YT Rockers | SSAC Headers | N* TB | TEP Trans | 3.29 FDR | Torsen LSD
DTM Tuned | Dual AeroForce | Solid Mounts | 255 Walbro Pump | Fuel Logs | GXP STB & Sway Bars | CSS Lowering Springs | GXP Brakes | Disabled DRL
Magnaflow Mufflers | Magnaflow Cat | GXP Seats & Trim | 35 % Tint | Cleared & Tinted Tails | repinS Retrofited Morimoto Mini H1 | 19" GT500 Wheels
'09 G8 GT "Abigail" Mods: Rotofab | LS3 Heads, Intake & Cam | Kooks LT | Solo Exhaust | Tien Springs w/ GXP Struts | Whiteline Swaybars | BMR Subframe Connectors
Achievements: Guinevere - 264k mi | 16.27 @ 84.10mph | March '11 COTM :: Chloe - 223k mi | 13.85 @ 102mph | January '09 COTM :: Abigail - 192k mi | 12.85 @ 112mph

Try running just the heat, without the defrost or the air conditioner running. Do both sides stay cool, or does one side work normally? The most likely culprit is the air mix actuator, but you should have one for each side. Both going bad would seem unusual.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Both sides are cold

How much do the actuators run and where are they located?

_________________

'93 SSE "Guinevere" RIP 1993 - 2019
'01 SSEi "Chloe" Mods: Intense FWI | GenV | WBS Intercooled | 3.2 MPS | 1.9 YT Rockers | SSAC Headers | N* TB | TEP Trans | 3.29 FDR | Torsen LSD
DTM Tuned | Dual AeroForce | Solid Mounts | 255 Walbro Pump | Fuel Logs | GXP STB & Sway Bars | CSS Lowering Springs | GXP Brakes | Disabled DRL
Magnaflow Mufflers | Magnaflow Cat | GXP Seats & Trim | 35 % Tint | Cleared & Tinted Tails | repinS Retrofited Morimoto Mini H1 | 19" GT500 Wheels
'09 G8 GT "Abigail" Mods: Rotofab | LS3 Heads, Intake & Cam | Kooks LT | Solo Exhaust | Tien Springs w/ GXP Struts | Whiteline Swaybars | BMR Subframe Connectors
Achievements: Guinevere - 264k mi | 16.27 @ 84.10mph | March '11 COTM :: Chloe - 223k mi | 13.85 @ 102mph | January '09 COTM :: Abigail - 192k mi | 12.85 @ 112mph

They are up inside the dash, and not an easy fix at all.

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Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

Start with easy stuff first. Is the engine temperature normal? Also, check the hoses for the heater core. Are they both hot, or is one colder than the other?

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Engine temps are normal 195. I'll go check the hose right now. But when I flushed the coolant out I pulled both heater hoses and made sure I had clear water coming out, so they're not clogged if that's what you're getting at.

[edit] Both hoses are warm. And when I turn the heater on I can feel the fluid flowing through them both.

_________________

'93 SSE "Guinevere" RIP 1993 - 2019
'01 SSEi "Chloe" Mods: Intense FWI | GenV | WBS Intercooled | 3.2 MPS | 1.9 YT Rockers | SSAC Headers | N* TB | TEP Trans | 3.29 FDR | Torsen LSD
DTM Tuned | Dual AeroForce | Solid Mounts | 255 Walbro Pump | Fuel Logs | GXP STB & Sway Bars | CSS Lowering Springs | GXP Brakes | Disabled DRL
Magnaflow Mufflers | Magnaflow Cat | GXP Seats & Trim | 35 % Tint | Cleared & Tinted Tails | repinS Retrofited Morimoto Mini H1 | 19" GT500 Wheels
'09 G8 GT "Abigail" Mods: Rotofab | LS3 Heads, Intake & Cam | Kooks LT | Solo Exhaust | Tien Springs w/ GXP Struts | Whiteline Swaybars | BMR Subframe Connectors
Achievements: Guinevere - 264k mi | 16.27 @ 84.10mph | March '11 COTM :: Chloe - 223k mi | 13.85 @ 102mph | January '09 COTM :: Abigail - 192k mi | 12.85 @ 112mph

You mention that you flushed the coolant. Is there air in the heater core?

The process for removing air after a drain is to run motor at something like 2500 for a few seconds and to repeat for a total of 5 times. The motor should be thoroughly warm with the thermostat open and the lower radiator hose warm IIRC from the service manual. The heater is the high point in the system so it is hardest to fill. I have a sloped driveway so I park with the heater core in the low direction to help burp the air out.

I don't believe there is any kind of valve in the heater core system to turn off water flow. So when you say you feel water flowing by holding the heater hoses, I wonder if you're feeling air/water mixing in the heater core.

I'm fairly certain that there is no air in the system. I've had that problem before.

_________________

'93 SSE "Guinevere" RIP 1993 - 2019
'01 SSEi "Chloe" Mods: Intense FWI | GenV | WBS Intercooled | 3.2 MPS | 1.9 YT Rockers | SSAC Headers | N* TB | TEP Trans | 3.29 FDR | Torsen LSD
DTM Tuned | Dual AeroForce | Solid Mounts | 255 Walbro Pump | Fuel Logs | GXP STB & Sway Bars | CSS Lowering Springs | GXP Brakes | Disabled DRL
Magnaflow Mufflers | Magnaflow Cat | GXP Seats & Trim | 35 % Tint | Cleared & Tinted Tails | repinS Retrofited Morimoto Mini H1 | 19" GT500 Wheels
'09 G8 GT "Abigail" Mods: Rotofab | LS3 Heads, Intake & Cam | Kooks LT | Solo Exhaust | Tien Springs w/ GXP Struts | Whiteline Swaybars | BMR Subframe Connectors
Achievements: Guinevere - 264k mi | 16.27 @ 84.10mph | March '11 COTM :: Chloe - 223k mi | 13.85 @ 102mph | January '09 COTM :: Abigail - 192k mi | 12.85 @ 112mph