SM If I were you I would take your concerns seriously, early intervention can be vital.
My DS didn't point, clap or wave, speak or play in the usual fashion - he too was/is obsessed with wheels.
I referred myself to Portage, by calling them and telling them I had some concerns which weren't being taken seriously (my HV used to say "it's not a race my dear!".
They 'taught' my DS to play, starting with the very basics, a wnaky (as I believe they are called on here) basket full of interesting things and descriptive play.
Descriptive play is fine if you are the only adult around but mortifying to do with an audience - you literally describe what child is doing, eg Master Scarlet has picked up the ball, the ball is smooth, Master scarlet has dropped the ball, he has picked up the wooden spoon and the peg, he is banging them on the floor etc This helps give them language and understand concepts.
We then built up to taking turns, posting, colour matching etc. Every week we were left a toy and a task to complete daily.
My DS at 20 months was 50% behind, by 30 months he was only 30% behind and I believe that the Portage input was vital to this.
Portage
There may be nothing wrong with your DS (mine doesn't have ASD just GDD) but it may be an idea to get a second opinion.