Co-op racing frustration

This is the first Horizon game I’ve gotten into and love the game so far. However, I’m very frustrated with co-op races. My car constantly stalls, or hesitates, while racing co-op races. I race on above average difficulty with the only assists being braking and automatic transmission. I do well in solo races against other drivatars, and PVP. It can’t be due to assisted braking because it happens in straight aways and areas where the driveline is blue. It’s very frustrating when you do great in solo races only to be the one always at the bottom in co-op races seeing “this race will end in 30 seconds” I’ve searched for an explanation and can’t find any. My only other gripe is in PVP, people in their S1’s and S2’s hate it when they wipe out and I pass them in my A class, so they feel the need to catch up to me and ram me off the road.