Has been happening to me in some races. Happened to me yesterday at Brands Hatch GP so many times it was unbearable. That was the only race I could participate in yesterday. It didn't happen to me today during the qualifying. I'll have to see if it happens to me today.
I didn't have ASM on or any other assists, except ABS, which obviously should not affect acceleration. Never happened to me before the newest update.
I am on the standard PS4, using the T-150, and it happened to me using the GT-R at Brands Hatch. It does not seem to be a wheel issue though, as when it happens, it still shows full on acceleration, rather it seems to be a very bad bug.