No heat inside, termostat?
#1
10-30-2018, 02:05 PM
No heat inside, termostat?
Hi. I just bought an A4 B5. I have no heat in the car. Temperature is almost at 65-70c always.
And it just blows cold air. Can it be the thermostat ?
And it just blows cold air. Can it be the thermostat ?
#2
11-01-2018, 12:06 AM
Look under your hood on the right (passenger) side and clipped to the (lower) inside of the radiator you will see a Green and Purple connector. That is for your A/C compressor. Unplug it/disconnect it and you should have super hot heat. That is a common problem with our cars.
#3
11-01-2018, 05:20 AM
Look under your hood on the right (passenger) side and clipped to the (lower) inside of the radiator you will see a Green and Purple connector. That is for your A/C compressor. Unplug it/disconnect it and you should have super hot heat. That is a common problem with our cars.
Thanks
#4
11-01-2018, 10:42 AM
That's what I do. It's cheaper than replacing the climate controller.
If for some reason you don't get super hot heat after doing that, then you also need to flush your heater core (another common issue with our cars). You can YouTube the process. It's easy and it's worth doing anyway.
G/L
If for some reason you don't get super hot heat after doing that, then you also need to flush your heater core (another common issue with our cars). You can YouTube the process. It's easy and it's worth doing anyway.
G/L
#5
11-01-2018, 01:49 PM
That's what I do. It's cheaper than replacing the climate controller.
If for some reason you don't get super hot heat after doing that, then you also need to flush your heater core (another common issue with our cars). You can YouTube the process. It's easy and it's worth doing anyway.
G/L
If for some reason you don't get super hot heat after doing that, then you also need to flush your heater core (another common issue with our cars). You can YouTube the process. It's easy and it's worth doing anyway.
G/L
Thanks again, i reply when success ^^
#7
11-06-2018, 03:33 AM
Update: I changed the thermostat yesterday. Filled up with new coolantfluid and drove home.
Engine temp was rising normal up to 90, but when i opened the hood the expansiontank spitting out huge amount of condensed coolantfluid from the "escape" pipe from the backside of the tank.
When it stopped, i had under MIN in the tank...
question: Airbubbles ?
Engine temp was rising normal up to 90, but when i opened the hood the expansiontank spitting out huge amount of condensed coolantfluid from the "escape" pipe from the backside of the tank.
When it stopped, i had under MIN in the tank...
question: Airbubbles ?
#8
11-06-2018, 07:09 AM
If, once the engines hot, like 90°C on the dashboard gauge, check both of the hoses that lead to the heater core, under the bonnet near the firewall, if they are both hot, then the heater cores OK.
You do need to bleed the air from the coolant system, there's some bleed screws depending on what engine you have. Though the one on the heater cores inlet hose should do most of it. Then later the coolant will burp some hot water, top it up again & let it cool down so it sucks the coolant into the engine and then drive again.
Check you air vents in the car, you can pull the grill out easy if you take your time, do it evenly & in small movements. If there's bits of black or grey foam in there, the foam that covers the flaps inside the heater core box have disintegrated & it's letting air thru the flaps & the only way to fix it is to take it out & re cover the flaps with new foam.
Ok, it's a very involved job, but I have done it. There's a bit of a write-up in one of my posts, no photos though.
You have to take everything under the dashboard out, glovebox & centre console, it's tedious & there's lots of bolts.
But. It's doable.
If your headlining has dropped, it's the same fault, the foams disintegrated, that's also doable. It just takes a lot of time. By the time you have done it, you won't want to do it again, ever. OR, you have just figured out how to make some spare ca$h by fixing other people's A4's..
The brake fluid resiviour & the oil dipstick funnel ( bright orange )& the crankcase ventilation hose fitting, part # 058103213 if it's a 1800 ADR or APT engine will also be perished & need replacing.
You do need to bleed the air from the coolant system, there's some bleed screws depending on what engine you have. Though the one on the heater cores inlet hose should do most of it. Then later the coolant will burp some hot water, top it up again & let it cool down so it sucks the coolant into the engine and then drive again.
Check you air vents in the car, you can pull the grill out easy if you take your time, do it evenly & in small movements. If there's bits of black or grey foam in there, the foam that covers the flaps inside the heater core box have disintegrated & it's letting air thru the flaps & the only way to fix it is to take it out & re cover the flaps with new foam.
Ok, it's a very involved job, but I have done it. There's a bit of a write-up in one of my posts, no photos though.
You have to take everything under the dashboard out, glovebox & centre console, it's tedious & there's lots of bolts.
But. It's doable.
If your headlining has dropped, it's the same fault, the foams disintegrated, that's also doable. It just takes a lot of time. By the time you have done it, you won't want to do it again, ever. OR, you have just figured out how to make some spare ca$h by fixing other people's A4's..
The brake fluid resiviour & the oil dipstick funnel ( bright orange )& the crankcase ventilation hose fitting, part # 058103213 if it's a 1800 ADR or APT engine will also be perished & need replacing.
#9
11-06-2018, 07:42 AM
If, once the engines hot, like 90°C on the dashboard gauge, check both of the hoses that lead to the heater core, under the bonnet near the firewall, if they are both hot, then the heater cores OK.
You do need to bleed the air from the coolant system, there's some bleed screws depending on what engine you have. Though the one on the heater cores inlet hose should do most of it. Then later the coolant will burp some hot water, top it up again & let it cool down so it sucks the coolant into the engine and then drive again.
Check you air vents in the car, you can pull the grill out easy if you take your time, do it evenly & in small movements. If there's bits of black or grey foam in there, the foam that covers the flaps inside the heater core box have disintegrated & it's letting air thru the flaps & the only way to fix it is to take it out & re cover the flaps with new foam.
Ok, it's a very involved job, but I have done it. There's a bit of a write-up in one of my posts, no photos though.
You have to take everything under the dashboard out, glovebox & centre console, it's tedious & there's lots of bolts.
But. It's doable.
If your headlining has dropped, it's the same fault, the foams disintegrated, that's also doable. It just takes a lot of time. By the time you have done it, you won't want to do it again, ever. OR, you have just figured out how to make some spare ca$h by fixing other people's A4's..
The brake fluid resiviour & the oil dipstick funnel ( bright orange )& the crankcase ventilation hose fitting, part # 058103213 if it's a 1800 ADR or APT engine will also be perished & need replacing.
You do need to bleed the air from the coolant system, there's some bleed screws depending on what engine you have. Though the one on the heater cores inlet hose should do most of it. Then later the coolant will burp some hot water, top it up again & let it cool down so it sucks the coolant into the engine and then drive again.
Check you air vents in the car, you can pull the grill out easy if you take your time, do it evenly & in small movements. If there's bits of black or grey foam in there, the foam that covers the flaps inside the heater core box have disintegrated & it's letting air thru the flaps & the only way to fix it is to take it out & re cover the flaps with new foam.
Ok, it's a very involved job, but I have done it. There's a bit of a write-up in one of my posts, no photos though.
You have to take everything under the dashboard out, glovebox & centre console, it's tedious & there's lots of bolts.
But. It's doable.
If your headlining has dropped, it's the same fault, the foams disintegrated, that's also doable. It just takes a lot of time. By the time you have done it, you won't want to do it again, ever. OR, you have just figured out how to make some spare ca$h by fixing other people's A4's..
The brake fluid resiviour & the oil dipstick funnel ( bright orange )& the crankcase ventilation hose fitting, part # 058103213 if it's a 1800 ADR or APT engine will also be perished & need replacing.
I just tried to bleed out the air from the inlet hose (AEB) engine, turned on the car, no water or air at all for about 10mins, when i squeeze the radiatorhose it comes air out of the "bleedinghole".
I think its ALOT of air that is trapped around the heatercore...or ?
I dont think it is the waterpump, its steady at 90C.
#10
11-07-2018, 05:03 AM
I haven't figured out the cooling system yet. It's really involved though.
like by checking # 49 & 51 on the climate control computer I get different temps, #49 seems similar to the dashboard gauge temp, but it's not exactly the same.
The fan motor temp switch is on the radiator hose near the radiator & is pretty much a whole seperate electric circuit from anything else.
I thinking there's a coolant system just to circulate coolant around only the engine, to get it up to temp evenly quicker.
Then when that's done, it might open valves & bring the heater coolant system into the circuit.
And then once that's happening the dash gauge goes up untill the thermostat opens & the radiator does the cooling.
And then.. the radiator needs a helping & the radiator fan turns on @ 90°C.
To bleed the heater core you should be running the engine at over 2000 rpm.
The whole Audi idea is a bit confusing, but I'm sure that if I knew exactly what was happening, I would see that it makes sense.
Most cars I have worked on use a little water thermostat valve, operated by a human inside the car, to control the temp of the water going thru the heater core.
Audi just have hot water running thru it all of the time and then control the amount of air going past it, and then blend that hot air with other cold air, so that the air inside the car is the correct temp. That's why there's so many temp sensors, 2 or 3 in the air box. 1 in the headlining, 1 in the centre console above the climate control, and a small motor/fan to drag air past it.
There's pics on the internet of where the coolant air bleed screws are, on my APT 2.4 litre, there's a hex screw under a cover, close to the radiator on the passenger ( right hand drive car) side, That one will burp some air.
But I'm thinking that in time, the heater core bleed air hole is the best one because it's higher, you need to rev the car a bit though. Just do it several times over several heat-cool cycles.
What's your engine 1.8 or V6? Was there any loose foam in the vents?
like by checking # 49 & 51 on the climate control computer I get different temps, #49 seems similar to the dashboard gauge temp, but it's not exactly the same.
The fan motor temp switch is on the radiator hose near the radiator & is pretty much a whole seperate electric circuit from anything else.
I thinking there's a coolant system just to circulate coolant around only the engine, to get it up to temp evenly quicker.
Then when that's done, it might open valves & bring the heater coolant system into the circuit.
And then once that's happening the dash gauge goes up untill the thermostat opens & the radiator does the cooling.
And then.. the radiator needs a helping & the radiator fan turns on @ 90°C.
To bleed the heater core you should be running the engine at over 2000 rpm.
The whole Audi idea is a bit confusing, but I'm sure that if I knew exactly what was happening, I would see that it makes sense.
Most cars I have worked on use a little water thermostat valve, operated by a human inside the car, to control the temp of the water going thru the heater core.
Audi just have hot water running thru it all of the time and then control the amount of air going past it, and then blend that hot air with other cold air, so that the air inside the car is the correct temp. That's why there's so many temp sensors, 2 or 3 in the air box. 1 in the headlining, 1 in the centre console above the climate control, and a small motor/fan to drag air past it.
There's pics on the internet of where the coolant air bleed screws are, on my APT 2.4 litre, there's a hex screw under a cover, close to the radiator on the passenger ( right hand drive car) side, That one will burp some air.
But I'm thinking that in time, the heater core bleed air hole is the best one because it's higher, you need to rev the car a bit though. Just do it several times over several heat-cool cycles.
What's your engine 1.8 or V6? Was there any loose foam in the vents?