1991 mazda 323 protoge sputtering

i have a 1991 323 and recently had a radiator hose go and it leaked fluid all over the engine and at the same time some fluid got sucked into the air box where the air filter and the air flow sensor are . I had it towed to the mecanic and after he fixed the hose the car would not start. he then replace the air flow sensor beacuse he said that anit freeze had got sucked in through there and he had found a puddle if it in there. the car now starts and runs but under load -like going up a hill, or when i try to accelerate quickly the car will buck and hesistate and sometimes stall. This happens more when it is cold out, even after it has warmed up. i thought it could be the plugs and wires and had them replaced and it still does it . when its warm outside (50 degrees or warmer) it doesn’t buck and stall. any ideas.

Thank You