Audi A3 Overheating / Problem - HELP HELP

[firestar2k3]

Hi all

Right, got an audi a3 2001 plate avu engine, had a waterpump 15k miles ago, cant remember if its a plastic impeller or metal one, had a thermostat last week, new temp switch and stuff and fan kicks in.

right i have no temp displayyy so i felt the pipes, lots of preassure and very hot to touch.

now, other day, went on the motorway, 70+ got home, rad is stone cold as is lower rad pipe, but other pipes hot and very preassurised,

no coolant loss, never boils over or anything.

got vag com, when heater on hot with air blowing getting around 90-96 degrees, when its on cold with no air blowing i get 108 which i assume is too hot,

having no dash readout does not help, thats the instrument cluster.

so issue is, airlock, bad thermostat, faulty waterpump, bad rad? blown h/g?

Please help.

 

[jim s3]

i would say air lock or thermostat

 

[NHN]

sounds like air lock to me as its not circulating as rad cold but internal pipes are boiling, I wouldnt risk it as is mate, fix then drive or you'll have an even bigger issue & an even emptier wallet

 

[afcjay]

sounds like a air lock
try running it with the water cap off and give the pipes a squeeze you may be lucky
if that dont work id recommend getting it looked at if the waters not circulating properly

 

[NHN]

Actually thats a ****** good idea, well thought fella as I remember doing this once or twice to test something on my old S3

 

[firestar2k3]

ok

some more info,

took it out, checked it, its brand new thermostat, works fine, put it back in took it for a spin local run for about 30mins lots of stop start, bottom hose gets hot and rad fan kicks in and rad gets hot too... when running vagcom driving i got a temp of 90, and with the heater on cold got 108. the day from the motorway i have no idea,

could this be a airlock?

had this issue, tried to fan/temp switches, and new thermostat
so either its airlocked
either the headgaskets gone
or waterpump is shot

am getting water return to the bottle from that hose and do get very hot heat from inside

dont know anyone relaible in london i can ask so im quite stuck...

 

[HTC]

I think by removing the thermostat and refitting it you have cleared your problem. You would have had to drain and add more coolant in the process.

Does sound like you had an airlock which you have inadvertently now fixed.

Water returning to the expansion tank indicate the pump is working which is all so good.

 

[NHN]

Well he sems to indicate he hasnt fixed it by doing this or am I reading it wrong.

 

[HTC]

I think you are right. I'm speed reading.

Ummmmmm, dunno

Go for the airlock check if so.

 

[firestar2k3]

hi, thanks for the useful responses,

checking today, i get on vagcom (dnt know the dash value as its supposed to be adjusted quite a bit)

now, started it drove it with both heater hot/cold, with vagcom plugged in,

the pipes get quite a bit of preassure, i dont know if its too much like if the hg is gone, but it can be squeezed, if i open the bottle quickly it rises a fair but but does not overflow,

right

when the temp set on cold, temp runs between 105-108,

when set on hot runs between 90-96

the fan kicks in, all pipes and rad get warm / hot and seems to have flow, either the mixture is a little weak or its a screwed up car,

to be honest i hate it, worst car i could have owned.

 

[Clach]

Give dean of four rings a call mate...he knows his stuff (i put his number on here somewhere), do a search under 'dean'

 

[HTC]

The pipes should get hot and pressurised. They will be very hard when the car is running. This is normal.

I can't get to my car at the moment, but ask people to log their water temps as a comparison. The reason the temp changes with heater settings is because you a directing the coolant through the interior heater matrix, which is extra cooling.

One thing to check, did you check the temp range on the thermostat? There are different temp ranges available. The same for a the rad fan switches.

If it's not overheating and running okay with the fans working, then it may fine.

 

[ttaalliibb]

Hi I also have a symilar problem with my a3 1.8t. I replaced a radiator water pump, thermostat and my car still kept to overheated. I also flush the engine with some flushing stuff.
Run the engine for about a 15 min and when rich a 94 degree then engine stops runing and then I need to wait until the engine cool down.
All pipes are wery hot exept one coming from radiator to thermostat.
I also been in a few mechanic to connect them with a computer and still nothing .
If any one have some ideas please let my known
Thanks

 

[JUS3IN]

did your old water pump impellas break up? could be lodged in the engine somewhere like on my old mk1 golf vr6 conversion?

 

[ttaalliibb]

Hi Possible. Becouse there is many black bits in the water.
I flush engine many times today and still nothing changed. How you found solve that problem on your car?

 

[JUS3IN]

didnt it always god hot sporadically afraid, the last owner removed some, i imagine a strip down would be need to be sure then would still be hard to be 100 percent it was all out... but may be a last resort for ya?

 

[ttaalliibb]

Ok thanks anyway.
I thing I don everything . I also strip a head of and using a syrine to remove water from a engine block. Hopefully they found something in audi garage

 

[JUS3IN]

a bit was stuck in my expansion tank return iirc...

 

[ttaalliibb]

Aha
No weekend I also will try to clean it under a high pressure and hopefully will work

 

[ttaalliibb]

Hi mate
Thanks for everything. I found what the problem was. Crank sensor was dammaged that why car stop runing when reach 92 degree. That was not a overheating problem... just a sensor