Problem with A4 heater and coolant system
#12
01-15-2012, 08:12 AM
New heater core seems to be better
So I decided to go "all in" and replace the heater core. This seems to have worked.
However,
I have been there before.
Now I must set the temperature almost to low to keep the air reasonable. The air also continues to blow hot and cold (really) the temperature varies somewhat which it didn't used to do.
So, we'll see.Good luck.
Barry
However,
I have been there before.
Now I must set the temperature almost to low to keep the air reasonable. The air also continues to blow hot and cold (really) the temperature varies somewhat which it didn't used to do.
So, we'll see.Good luck.
Barry
#13
12-09-2012, 04:20 PM
I have a 2001 A4 1.8 with heater problems as well but it will always warm up after continued driving. When it is cold and the climate control is on auto the air blows cold or cool even when the engine temperature shows that it has warmed up. If I direct the air to the defrost or vent the air is much warmer.
Does anyone have any thoughts on this?
Does anyone have any thoughts on this?
#14
03-21-2013, 08:00 AM
if temp reading high but engine does not seem to be to hot check the electrical bonding(earth)strap between engine and chassis remove and check for corrosion don't assume that because it looks alright on the surface that it is ok
#15
04-11-2013, 07:10 PM
I have an a4 1.8t and my heater doesn't blow very hard at low speeds and at higher speeds never gets very hot, the mechanic said replace timing belt or water pump I think they are just trying to get abunch of money from me, any thoughts?
#16
04-19-2013, 08:40 PM
#17
11-10-2013, 08:55 AM
Empty garage
Hi can you shed light on how you fixed the heater problem
Mine is doing the same thing. hot when at idle or driving below 40mph, even when temp gauge saying 90 deg, over 40 mph it then blows cold.
Mine is doing the same thing. hot when at idle or driving below 40mph, even when temp gauge saying 90 deg, over 40 mph it then blows cold.
Last edited by stevegrasshopper; 11-10-2013 at 09:04 AM.
#18
12-29-2013, 02:06 PM
I have a problem with my heating system inside the car which is linked to the cooling system somehow. I have a 2002 A4 1.9TDi, when I drive the car at low rev's or sit idling I get heat inside the car, when I start driving at normal 60mph, intermittently I lose hot air inside. I also notice the engine temperature gauge rises when the hot air turns cold and vice versa (climate control set on Hi) although only when driving not sitting stationary.
I have had the water pump changed and the thermostat which has not helped.
I completely flushed (and reverse flushed) through the entire system 2 days ago from the top and the bottom of the radiator and through the heater matrix but it still does the same problem. There did not seem to be any restrictions when flushing.
Additionally, there is no signs of oil in the coolant or water/ coolant in the oil.
Oh, also, after driving, the temperature of the top radiator hose is boiling hot whilst the bottom one is cold. Both hoses in and out of the heater matrix/ core are hot. It would seem that for some reason there is an intermittent blockage in the system or there is some sensor in the system that shuts something off. Although not fully knowing everything about the system I'm kind of stumped for now. My mechanic is also stumped after replacing the water pump and thermostat. His next step was going to be replacing the radiator but I didn't want anymore time spent ont he car at my expense. The last bill was quite hefty!!! especially just before christmas
Does anybody have any ideas? I have seen lots of these forums with people with similar problems, although nobody has come up with a definitive answer. If I do get a solution to this, I fully intend going through a lot of these forums and updating them with the solution to my problem.
I have had the water pump changed and the thermostat which has not helped.
I completely flushed (and reverse flushed) through the entire system 2 days ago from the top and the bottom of the radiator and through the heater matrix but it still does the same problem. There did not seem to be any restrictions when flushing.
Additionally, there is no signs of oil in the coolant or water/ coolant in the oil.
Oh, also, after driving, the temperature of the top radiator hose is boiling hot whilst the bottom one is cold. Both hoses in and out of the heater matrix/ core are hot. It would seem that for some reason there is an intermittent blockage in the system or there is some sensor in the system that shuts something off. Although not fully knowing everything about the system I'm kind of stumped for now. My mechanic is also stumped after replacing the water pump and thermostat. His next step was going to be replacing the radiator but I didn't want anymore time spent ont he car at my expense. The last bill was quite hefty!!! especially just before christmas
Does anybody have any ideas? I have seen lots of these forums with people with similar problems, although nobody has come up with a definitive answer. If I do get a solution to this, I fully intend going through a lot of these forums and updating them with the solution to my problem.
I too changed the thermostat but this is were I think everything is going wrong, I am told that there are two different specification thermostats for the Audi A4, and the only identification I can advise to seperate them is that one stat has a jiggle valve and the other does not.
My car as far as I can remember was OK before I changed the coolant and stat, and I am now thinking that the stat is the wrong one fitted, i.e. it opens too soon and low temperature, thus a diesel will not attain normal temperature.
Try to assertain the correct type of stat for these models.
#19
10-27-2019, 03:48 PM
I have a problem with my heating system inside the car which is linked to the cooling system somehow. I have a 2002 A4 1.9TDi, when I drive the car at low rev's or sit idling I get heat inside the car, when I start driving at normal 60mph, intermittently I lose hot air inside. I also notice the engine temperature gauge rises when the hot air turns cold and vice versa (climate control set on Hi) although only when driving not sitting stationary.
I have had the water pump changed and the thermostat which has not helped.
I completely flushed (and reverse flushed) through the entire system 2 days ago from the top and the bottom of the radiator and through the heater matrix but it still does the same problem. There did not seem to be any restrictions when flushing.
Additionally, there is no signs of oil in the coolant or water/ coolant in the oil.
Oh, also, after driving, the temperature of the top radiator hose is boiling hot whilst the bottom one is cold. Both hoses in and out of the heater matrix/ core are hot. It would seem that for some reason there is an intermittent blockage in the system or there is some sensor in the system that shuts something off. Although not fully knowing everything about the system I'm kind of stumped for now. My mechanic is also stumped after replacing the water pump and thermostat. His next step was going to be replacing the radiator but I didn't want anymore time spent ont he car at my expense. The last bill was quite hefty!!! especially just before christmas
Does anybody have any ideas? I have seen lots of these forums with people with similar problems, although nobody has come up with a definitive answer. If I do get a solution to this, I fully intend going through a lot of these forums and updating them with the solution to my problem.
I have had the water pump changed and the thermostat which has not helped.
I completely flushed (and reverse flushed) through the entire system 2 days ago from the top and the bottom of the radiator and through the heater matrix but it still does the same problem. There did not seem to be any restrictions when flushing.
Additionally, there is no signs of oil in the coolant or water/ coolant in the oil.
Oh, also, after driving, the temperature of the top radiator hose is boiling hot whilst the bottom one is cold. Both hoses in and out of the heater matrix/ core are hot. It would seem that for some reason there is an intermittent blockage in the system or there is some sensor in the system that shuts something off. Although not fully knowing everything about the system I'm kind of stumped for now. My mechanic is also stumped after replacing the water pump and thermostat. His next step was going to be replacing the radiator but I didn't want anymore time spent ont he car at my expense. The last bill was quite hefty!!! especially just before christmas
Does anybody have any ideas? I have seen lots of these forums with people with similar problems, although nobody has come up with a definitive answer. If I do get a solution to this, I fully intend going through a lot of these forums and updating them with the solution to my problem.
thanks
Thread
Thread Starter
Forum
Replies
Last Post
gregp1962
Audi A4
22
12-21-2006 07:01 PM
