I have been on these forums for a few months now as I slowly try and get our Audi running great or figuring out of its time to just let it go. Bare with me as I have told this before and some of you have read and helped, and know I am not good at explaining all of these things in proper terms ha. Anyways, we bought a 2002 Audi A6 3.0L, Quattro automatic, v6 in February. When we got it we were warned it had a small oil leak. Still does but not really the problem at least I doubt it is the problem. Shortly after buying it we got an oil change and all the other “tune up” type work. Shortly after this we had a problem where when we started to pick up speed the car would shake and check engine would flash, this was eventually fixed by replacing 4/6 engine coil packs, we were told two of them had recently been replaced when we bought it. Ran fine. Then we blew a new tire. Then we had an issue that was believed to be in the ignition. Like the key wasn’t turning what needed to be turned all the way to catch and start the car. So we had the whole thing replaced. The mechanic motioned to the steering wheel saying just about everything had been replaced. Then our car kept not wanting to turn on, we were told it was our alternator. Had that replaced. Then a shortly after this it wouldn’t start again. I was tired of this happening and my faith in these mechanics was dwindling, with the help of someone on these forums I narrowed it down to simply the batteries in my key fob being replaced. $4. Anyways, it runs right now but I’m trying to plan for next problem. I’m thinking that next problem is our transmission but I’m clealry no expert. What I find odd when driving the car is it will struggle or take a while to switch into next gear. It’ll rev high and then not jolt abruptly into the next gear but maybe a little rough depending on how hard you’re trying to force it, but usually just switches normally and takes off smooth and normal. Sometimes when I first turn it on and it is really cold (we live in Colorado) it will idle high and CEL will flash but it’ll stop by the time we leave our apartment parking lot. This one I feel is explained by one of the codes I got so that helps just need to know what I should do to fix it.

Here are the codes (auto zone)
P0300 - random/multiple cylinder misfire
P0492 - secondary air injection system air flow too low
P0491 - bank 1 secondary air system air flow too low
P0421 - warm up catalyst bank 1 efficiency below threshold
P0431- warm up catalyst system efficiency bank 2 below threshold
P0303, P0306, P0301,P0302, P0304- cylinders 3,6,1,2,4 misfire detected.
P1296- cooling system malfunction

when he first tried about the first 3-4 times it wouldn’t pick up any codes, then said it did, but didn’t, then finally these. I’m sure it was just their tools but figured I would bring this up. Also, Monday I am going to have the transmission looked at, will update then as well.

However i I do not really know what to look into first, and what to start replacing first. Please help me out and let me know what I should do with this information!