Hi there — trying my best to learn the insides of these cars. Replaced the radiator and oil cooler on my 2002 93 turbo hatchback manual. Started it up for 15-20 mins with no leaks and then decided to drive it home from my brothers. Got around the block and everything was good. When I got into third gear (on a sight incline) the turbo gauge started making big leaps from yellow to red and the engine stalled. I could not get the car past second gear after this and it would not idle well—I had to give it a bit of fuel to keep it from stalling. Reverse worked okay. I got it back to my brothers house in reverse. I was wondering if someone might be able to help me understand what’s going on. Thanks!