Engine temperature and warm up time

You got it Dag ;)

Joking apart get that stuck to the front of the rad, start her up, drive for a few mile, if you hit 90 degrees C, case solved!!!
 
Don't be soooo daft guys, in this weather it would get wet n fall off!! Besides my warranty would be then void as I've then modified the car......driving the car backwards is the only way forward me thinks :)
 
Hope everything turns out well on the 27th
Blocking off the front was just a fun comment... but remember air intake is at the front also the aftercooler.
 
Me too doug. Otherwise ill have to get me socket set out n do it me self.

Thinking about lease cars for the future.
 
Doug might have been joking, i wasnt though.

Get a piece of card and slide it infront of the radiator. The card will stop the air flow through the radiator and regardless of if the stat is stuck open you will see a temperatue rise. If you get to the normal 90, pull it out again and if it drops back down to 70, then your stat is stuck open. You can then go back to the garage and get it swapped out with confidence that its not going to be at your cost.
 
Start the engine from cold and leave it in neutral.

The temperature gauge should slowly rise and rise up to around 90, then as the thermostat opens it should level off or drop a little.

Then after a while the temperature will start to rise again and reach a temperature where the fan will come on.

Then the temperature should slowly drop and the fan will stop.

Then it will cycle like this forever.

If you then go for a drive, the temperature should not fall too far. If it does, the thermostat is stuck open.
 
How many of you guys have this car. 2008 a4 2.0 tdi 143? What are yours like?
 
How many of you guys have this car. 2008 a4 2.0 tdi 143? What are yours like?
.

My A4 is January 2006 140hp, 43K power machine and fully original except I have had the battery changed under warranty, dealer S/H.
This car will be departing soon for new A3, I hope this meets all the requirements....
 
Hi, I have this car. And I do notice the engine cools down with light driving in cold weather. Such as long, steep, declines, the temperature dial moves right down. As soon I put the engine under any load again though it moves back up. I found it strange at first as previous cars I have had got Upto temperature and stay fixed there. If you are driving normally on a motorway and the engine won't reach temperature something is definitely wrong though
 
It's the stat I think. Stuck open or slow to react. Could be its just crap, made with cheap materials.....u seen the price of copper?!
 
Here's the latest. Another Audi garage says there is a problem. He asked my authorisation to check the water pump but I said its a warranty fault. Audi uk then phoned me and DIDN'T HAVE A CLUE WHERE SHE WAS nevermind be of help. She started saying it wasn't covered and I I had to pay then rather rudely hung up. (I recorded the call!) I then got a call back from the garage who now have authorisation to check the pump but nothing else. He also said he don't think the thermostat was changed??? The case continues!!
 
You probably spoke to the same person that spoke to me about a query. Useless and rude to say the least. Not customer service in any way shape or form, hope you get it sorted :)
 
It was a while back so i cannot remember but if it was not then they have two rude customer service people. A shame really as their jobs are provided by people like us that buy Audis. I never considered BMW but may next time. Customer service is no.1 for me when an issue is present. They failed and should look to resolve it quickly, shame as i love my Audi.

cheers

n0v
 
The other audi garage found an air lock in the cooling system. You would think these cars would have an automatic bleed valve fitted on the top hose ?
 
Blimey, never saw that coming ...you'd think Audi would bleed it properly if they've opened up the middle of the system to remove a part for checking\replacing.
 
Question is, if this has been the problem all along and the stat was changed then the problem came back how is the air getting there?
 
Strange comment from the Audi dealership.
If the car had any air lock after installing the stat, the car would have overheated as the cooling system is spec'd for around 10% in reserve for clogging and wear.
My experience in engines with air lock will overheat quickly and throw the water out as the result, that's why you have the small hose attached to the expansion bottle to let any air out of the system during normal operation. This should have been addressed during the road test and checks after the job being completed.
Air can only get in the cooling system if there is a leak in the compression/combustion cycle, again this will discolour the cooling water, anything else will result in water loss.
I find it hard to understand if you drain 20 litres from a cooling system WHY only fill it with 18 litres this again is bad mechanics or people just not knowing.
 
Maybe the stealers never replaced it in the first place. Sounds like a stuck thermostat to me.
temp should stay at a constant 90, uphill or down. Take it back to the stealerS and make them
fix it.
 
Doug if it is the head gasket what do you think my chances are of having it replaced. The car was in warranty when I reported a problem but warranty is out now!
 
Question is, if this has been the problem all along and the stat was changed then the problem came back how is the air getting there?

Hi there, just joined the forum, and noticed your fault symptoms, I had similar on a Mk5 Golf GTI which I have had from new, just like many I assumed it was the thermostat remaining open, I had the stat replaced but the guy changing the stat said another item was was showing a slight leak, so he replaced that, looking at the stat, it looked closed just like the new one, anyways he replaced both and I'm pleased to say the engine reaches 90c on the dial again within 17 minutes and that is with sub or just above 0c ambient temperatures, I don't know what the part is called but here is a pic of it on the right

DSC_1156_zps2da64946.jpg
 
Did you resolve your problem?

I've just bought a 2008 avant 143 and have noticed mine takes a few minutes longer than expected to warm up, just over 10 minutes roughly. I will be changing the thermostat when i change the timing belt this year and expect this time will drop. Few comments on your problem having read this thread:

- When the engine temp is within a normal range (approx 82 and 95 degrees) the pointer will point at 90. If the engine goes outside this range then the pointer starts to move. If you plug in VCDS whilst driving you will see this. In my old S3 you can display actual engine temp through the climate display and observe this. Thermostats actually have 87 degrees written on them but i think the germans think it is neater to tell you its 90 degrees.

- The symptoms point towards thermostat failure. People do experience new thermostats failing from new so this is a possibility if it has already been changed. Some thermostats fail stuck open prevent the car warming up and some stuck closed causing overheating. A thermostat is one part its worth buying from the dealer despite being 3-4 times the cost to ECP.

-What mileage and age is the car? Has the waterpump been changed? The impellers on the waterpump can gradually break up rather than fail completely. This happened on my s3, causing gurgling and overflow into the header tank you described. This is why waterpumps get replaced every 5 years or 75k with the timing belt.

If you are confident that the thermostat is ok i would be looking at the waterpump next. Temp sender fault is a possibility but would normally appear on the diagnostics as having an intermittent fault.
 
It's fine in the summer but not in winter. But only on short journeys. So I've told the wife not to use 6th when going to work to help heat the engine faster.
 
Hello,
first sory for my bad english, i have bought a4 b8 avant 2.0tdi, and i have the same problem with my car, working temperature is changing from 60 to 90 depends on my driving, i have chandged zhe termostat and water pump, my mehanic cant fix it, did you fixsed yours? thanks
 
It's fine in the summer but not in winter. But only on short journeys. So I've told the wife not to use 6th when going to work to help heat the engine faster.
Hello,
first sory for my bad english, i have bought a4 b8 avant 2.0tdi, and i have the same problem with my car, working temperature is changing from 60 to 90 depends on my driving, i have chandged zhe termostat and water pump, my mehanic cant fix it, did you fixsed yours? thanks
 
I had a mk5 GTI which was absolutely fine in summer, rose to 90 and stayed there. In winter it was a different story, it would get to say 70 and fluctuate. First I changed the sensor then the main thermostat but the problem remained. Otherwise the car ran absolutely fine and various garages told me this was 'normal' but I knew it wasn't as VAG design the gauge software to display 90 even if its fluctuating around within a normal tolerance. Others on GTI forums said their cars behaved normally. I was totally baffled by this as I couldn't think what else it could be and eventually sold the car on with this fault.

Some time later as more people had the same issue it came to be known on various forums that the cooling system was quite complex and infact it had some sort of two stage thermostat set up, there was a smaller stat somewhere that isolated a part of the system - the idea being to encourage fast heat up by progressively opening the circuit during warm up. The issue many people had was this smaller stat was failing in the open position.

Not sure if its the same set up on your car, it wouldn't surprise me if it was since its likely been designed to warm up as fast as possible and VAG replicate a lot of technology across all their vehicles.
 
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Did your Golf have a DSG gearbox ?. I think you are talking about the thermostat that controls coolant flow to that. These seem to fail but not only on the Golfs as you say other cars with DSG gearboxs have the same stat. Not sure if this just applys to transverse engines though.
The DSG box in the B8 has an oil cooler I think so possibly not connected into the cooling system.
http://www.mk5golfgti.co.uk/forum/index.php?topic=78341.0
 
No it didn't - it was a manual. It still seems to suggest there that manual cars had an inline thermostat (total of two 'stats') and the DSG models indeed had an extra one.

But the post above describes exactly the issues I had with the Golf.

It might well be the case that Audi / the OP's engine doesn't use the same system but worth investigating. At the time I had the issue no one, now even the VW dealer, seems to know about there being additional thermostats present.
 
Hi guys just a thought on the bmw it had a main stat obviously, And it also had a stat included in the EGR cooler , EG ITUM 20 IN dieseldougs post , this was replaced along with the main stat as this was a big problem , on these cars. with the EGR coolant stat being stuck
This would quicken the buld up of soot in the EGR , hence low MPG and more dpf regens pluss por mpg also fan on a lot more
 
My 2008 143 engine done it loads. Even after - new water pump, new stat, complete drain and refill, and the courtesy car done it too. My 2010 170 doesn't do it. Personally I think there must be a point in the cooling system that creates an air pocket. Somewhere near the temp sensor that feeds the dash. It's defo not an electrical fault as you can feel the difference in the cabin heater temperature when on max.
 
Hello, i changed today again thermostat end the plastic cover, the same again, so far i changed water punp, sensor, stat , stat cover, tomorow i am driving tje car to onother audi garage, when i drive fast or car works in place temperature is normal 90, when i drive slow or downhill temperature 60
 
I asked about this when my car was serviced. There is a technical bulletin from Audi about it.
Because of a very good effectiveness of the engine in the low rev range, little engine heat is passed on to the coolant. At low outside temperatures the coolant temperature does not reach 90c. If the heating is used, the coolant loses further heat depending on the blower level. As a result, the coolant temperature can fluctuate between 50 and 90c.
 
Hello, it is fixsed, now temperature is 90, constantly, audi servise change small termostat on the water pipe, s this car 2.0 tdi, cr hawe 2 stats, they charged 300€ the part 150€ and work 150, they olso did not now for this they discover it after 3 days, this small stat coms with water pipes in complet, i put the pictures
 
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Changed parts
 

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Just had it in today and basically it's "its normal for this engine temperature to fluctuate when outside temperature drops below 5deg C. This is due to the engine being so efficient. This can change due to driving style, cabin heater settings and load."
That's what the Audi technical bulletin says. I queried how my B8.5 behaved compared to my B8.
So now I have a blank fitted between the radiator and cooler, just slots into place.
 
I asked about this when my car was serviced. There is a technical bulletin from Audi about it.
Because of a very good effectiveness of the engine in the low rev range, little engine heat is passed on to the coolant. At low outside temperatures the coolant temperature does not reach 90c. If the heating is used, the coolant loses further heat depending on the blower level. As a result, the coolant temperature can fluctuate between 50 and 90c.


I was given the same shpeal but couldn't take a copy. If this is the case then that would indicate the coolant system is too big or the stat is not effective. It's a well known fact that deisel burns most effectively when the engine is at optimum temperature. If that wasn't the case then every vehicle manufacturer would not have their engines run at 90deg C. VW group want consumers to regain their trust?? Stop filling us full of poop!!! Simple really...
 
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When mine goes in for it's next service I'll ask about that second thermostat.
Do you have a part number? Any idea what it feeds?
 
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You'll know when the egr does a regen. You'll be able to feel the heat when you get out of the car!