To improve the low-level performance of the MiG-3, one aircraft was tested with the AM-38 engine used by the Il-2 in July 1941. It proved to be faster than the normal MiG-3 at sea level and was more maneuverable as well. It was recommended for production after passing its State acceptance trials in September, provided that a cure for the engine's tendency to overheat in ambient temperatures above was found. However the sole prototype was shot down on 5 October during flight tests and it was decided not to proceed with the idea as all AM-38 production was allocated to the Il-2. Ironically, later in the war, about 80 MiG-3s were reengined with AM-38s to make them airworthy again. Many of these were rearmed with two 20 mm ShVAK cannon as well.