so are you saying that the thermo. is aftermarket or the ETCS??? By aftermarket do you mean OEM replacement?? Not from the Audi dealer???
A bad MAF will make you run rich, try cleaning it.

 

ive only changed my air filter recently, im running a neuspeed pod filter, also the thermo is some no name one made for fords etc but fits the car...

ETC is genuine audi...

 

I wasnt aware that thermostats were universal between differnt cars ??

 

If there's any question on your NON OEM thermostat... just get the correct one to eliminate factors of your rich condition. Thermostats are cheap... might as well get the correctly specified one.

 

I agree... But i dont see how it would cause you to run rich. Is your MAF connected with your neuspeed intake? Did your intake require oiling?? Sometimes if you over oil intake filters it screws up your MAF which will cause you to run rich.

 

It could be that his non-OEM thermostat is a colder one, which can cause your car to constantly run rich because the ECU doesn't get a normal operating temp range.

 

That makes sense!!!!!!

 

I have fitted many aftermarket stats without any issues perhaps the fault is wiring short, any fault codes??

 

if the thermostat was making it seem too cold the car wouldnt run rich.
if anything it would just make the car idle at a higher rpm. like when you first
start your car in the morning. to warm the engine up the it will give more
fuel and raise the rpm's. but it wont just run rich.


a fuel problem isnt going to come from a coolant problem. or vice versa.

check elsewhere.

is it idling normal. smells like gas (it should if its really running rich),
are all vacuum lines hooked up or plugged. are all wires making conatact.
wiggle things around. while its running and listen for changes in idle.
good ones of course. what like 850-900 rpm at idle.