Triumph: I've done the pan removal, pump replacement. Altair 4 is right, it's not fun nor easy on the 1.8T.
You have a classic case of symptoms for sludge. Whatever you do PULEEZE don't do one of the quick flushes or take it to an oil change place that does the power flush.

uke: That cost me a pump and a turbo and almost cost my top end. It dumps all the stuff from the whole engine down to the bottom and it instantly clogs the oil intake screen. Here is what I would do in your situation:
Get two bottles of Auto-RX (
www.Auto-RX.com) and follow their heavy sludge removal procedure. Auto-RX is perfectly safe and it absolutely works. It will remove your sludge all over the engine and do it will clean up the ring packs and you'll get smoothness and power back. This product works... it just takes time.
Alternately, here's what I would do if I wanted to attack the sludge in the pan instantly and then do the Auto-RX for the top end:
-Drop the oil.
-Put the plug back in.
-Pour in 3 qts of kerosene. DO NOT START THE ENGINE.
-Take off the filler cap so vapors can escape.
-Let it sit overnight, then dump the kero. LOTS of junk will come out.
-Repeat above steps again for a second clean and rinse.
-Pour another couple quarts through with the drain open to purge the loose stuff. Let it thoroughly drain.
-Put the plug back in and put in some cheapo oil.
-Run the engine for 5 mins at idle until it warms up.
-Drop the oil and the filter.
-Replace oil with decent dino oil and run Auto-RX for the 1500 mile cleaning phase and follow their directions.
The kero trick has been used for a long time by mechanics. In fact the quickie flushes are mostly kero. They're just too harsh and risky in this situation to risk starting the engine. Bad for seals too.
Auto-RX has worked really, really well for me not only in my Passat but in my Windstar, and others on CB5 have used it with excellent results. The ONLY risk with using it is that if you are on the cusp of a total sludgeup and pump failure it may be too slow, as it takes 3500 miles for one full cycle of cleaning and rinsing. Sounds to me like you may not be quite there yet.
Since I've got mine cleaned out I'm going to keep 3oz of Auto-RX in each oil change to keep the engine totally clean. Sludge never again! It's a really destructive pain!