Gti - Volkswagen :: 2003 - Shudder While Shifting To 3rd Gear - Smaller Shudder Shifting To 4th

I had recently purchased a 2003 golf gti AUTOMATIC (with optional shifter) with a 1.8 turbo 4 cylinder engine. The vehicle has 139,000 miles on it. Before purchasing, I had a mechanic come out and look at the vehicle for a pre-purchase inspection, and ran the code P0303 (cylinder 3 misfire) which without test driving, told me that is what caused the shift shudder I noticed when I had test driven it a previous day. He told me the coil packs were in good condition by looking at the top of them, and told me if I replace the spark plugs, the issue should go away.

I feel it is important to mention that he had also run codes on the transmission and nothing came up. Taking it home, this morning I had replaced the spark plugs and driven it for about an hour both regularly and aggressively to test it. The problem is still there, and I was really hoping that there is a solution to this problem, because everything else on the car is beautiful, while being my dream car, I just want it to work as well as I know it can. To be more descriptive, when shifting to 3rd the whole car feels basically like it is tripping over itself before successfully shifting.