Stiff gear box?

Hej, I am assuming you have a manual gearbox. Mine is always a bit notchy from cold on my 2.0t. I understood it was a characteristic of the B7 manuals and nothing to be worried about. I have read a few other posts stating similar issues.
As for your thermostat....sounds like you need to replace it. If it's not bang on that 90c ....it needs replacing.

Cheers
A

No worries, you'll get the hang of it sooner than later!....Sorry don't have the part number but someone else will post it am sure. Please only buy a proper VAG one from Audi...don't buy a Fleabay knock off. You have to buy the complete assembly...which from memory isn't cheap...about 50 or more of your Engrish quids....but has to be done! You will notice a vast improvement on your mpg as a result.

Cheers
A

Right I might be able to help with this one.

Firstly with regards to the temp issue. If the gauge is getting to 90 then going down it could be the sensor rather than the thermostat.

If you have the ability to scan your vehicle it will be a lot easier to diagnose.

The sensors are quite prone to being faulty.

If you do come to the conclusion its the thermostat the part number is 06D121111G - £23 Trade, £32 Retail.
The coolant sensor on the other hand consist of the following:
Coolant Sensor - 06a919501A - £35
Coolant retain clip - 032121142 - £1 (this does not need to be purchased if you dont break your exisiting one on removal)
Coolant Rubber seal - N90316802 - £1.5 this will be necessary.

With regards to the gearbox its the same for me. Depending on your mileage you could consider changing your gearbox fluid even thou audi specify its "sealed for life" I dont believe this because if that was the case it woudlnt have a drain and filler hole. Audi recommend every changes every 40000 miles.

What I found with my gearbox was putting in a lower temp oil basically the oil would be thinner on start up. Rather than it being thick if you can make sense of that.

Hi guys, if you read my build thread, link on the end of my signature, it details both the temp fluctuation issue fixed and and gearbox oil change I had done. My gear shift feels like new!

My 2006 A4 1.8T Quattro has a slightly stiff gearchange. I have changed the oil using OE VAG stuff and
its still quite stiff from cold.
I also have an E39 M5 which is having a winter hibernation and that has a horrendous manual shift from cold.
The OP said he cannot engage 1st at all unless he goes through other gears first.
I would think this would not fall under the realm of being "normal" or a "characteristic" of B7 "manuals"`
Its one thing have a stiff shift and quite another not being able to engage 1st