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2001 Passat 1.8
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2001 Passat 1.8 with 165,000 on it has no heat. I changed the heater core lines and bleeder the cool lines thinking it was my problem because I had a leak.all of my switches on my control panel work and I checked the blue and red blender doors arms and they move correctly. Cabin air filter was replaced. Does anyone have any advice?
 

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2005 Wagon 1.8/tip/4-mo
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Sometimes with my passats of the same era I'd had to take a 10 - 20 minute drive on the highway to get rid of an air pocket when I've replaced hoses, etc. Have you taken a long highway speed drive with it since the change?

With that age, it is possible the heater core itself could be mostly plugged too...changing that is something I've left to mechanics as it's a lot of work.
 

· If I See a Problem I Tell Someone
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Do both the heater core hoses get hot after driving it? If not, the core is probably clogged up.
If they do, unscrew the coolant reservoir and hang it from the hood strut with a bungee cord. Start the engine and let it warm up. Then turn on the heat to max temp and max speed ( I'm guessing you don't have Climatronic). Step on the gas until the RPMs reach 2500 and hold it there. Does the air get any warmer?
 

· PassatWorld Elder
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Try doing what @Tortelious mentioned.

On the surface this sounds like a clogged heater core. Common issue.
If the air gets warmer when revving the engine then it's a clogged heater core.
Assuming your water pump impeller isn't coming apart.
You could do a reverse flush on the heater core itself. That will buy you some extra time so you don't have to tear out the dash for heater core replacement.
Did the same to my 1998 GLS for a couple of years. Then I moved to the desert. Now I just ignore it because I don't need it.
 
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· I Know Stuff
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Bleed the coolant properly.
Fill reservoir and leave cap off.
Remove screws from reservoir and disconnect the sensor plug from bottom of reservoir, and raise the reservoir as high as you can.
Release clamp on heater core hose with bleed hole, and move the hose far enough to open the bleed hole.
When there is a continuous steady flow of coolant out of the bleed hole, re-fit & clamp the hose.
Re-fit all removed items, and top-up if required.

Do NOT run the engine at anytime during this process.
Coolant temperature, or heater on or off, have no affect on bleeding.
 

· If I See a Problem I Tell Someone
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@S10aromeo
I don't know if you did or not, but don't combine fixes. Sure, if you have the engine running while you expose the bleed hole in the heater core hose and give it some gas, that stream of coolant will shoot out high enough to hit the hood. But as soon as you let off the gas, that same stream will reverse course and suck in air. Don't ask how I know this ;).
I don't know about the 1.8, but the 2.8 also has a couple bleed screws on the engine itself. Do some Googling or wait for someone here to chime in if so & location.

As an alternative, you could hang the coolant tank and remove the cap. Start the engine and let it run - w/o that cap it won't pressurize. That will also bleed the system. And once it gets up to operating temp, see what kind of heat you have from the vents.
 

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any ideas?
Check the coolant reservoir. I had the same issue but fixed it this week since fall is upon us. My issue ended up being the coolant reservoir. It had a small spit where the screw in cap o ring seals against the metal band just inside the tank. This was causing my coolant system to not fully pressurize. I now have great heat. My Passat is a 1.8t wagon, manual, 4 motion.
 

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@S10aromeo
I don't know if you did or not, but don't combine fixes. Sure, if you have the engine running while you expose the bleed hole in the heater core hose and give it some gas, that stream of coolant will shoot out high enough to hit the hood. But as soon as you let off the gas, that same stream will reverse course and suck in air. Don't ask how I know this ;).
I don't know about the 1.8, but the 2.8 also has a couple bleed screws on the engine itself. Do some Googling or wait for someone here to chime in if so & location.

As an alternative, you could hang the coolant tank and remove the cap. Start the engine and let it run - w/o that cap it won't pressurize. That will also bleed the system. And once it gets up to operating temp, see what kind of heat you have from the vents.
The 1.8 only has the single bleed point.

Your alternative method does not work, nothing happens with that method that doesn't happen every time the car is driven.
You cannot bleed the system with the engine running, or without opening the bleeder.
 

· If I See a Problem I Tell Someone
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The 1.8 only has the single bleed point.

Your alternative method does not work, nothing happens with that method that doesn't happen every time the car is driven.
You cannot bleed the system with the engine running, or without opening the bleeder.
Well, I don't usually drive my car with the hood open and the coolant expansion tank hanging from it, but perhaps you have.
 
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