Well, i think i found the issue, was about motion vectors on the cars physics, due they still using the 5.1 plugin instead 5.2. But still no clear if this is the issue.
What i not understand is why with Temporal.Quality 1 does fine but not with 2 ¿?
Also With substepping=false TAA works fine, but if true, TAA goes bad again. Very weird ¿?
WIll wait for the 5.2 plugin release to see if still happens.