how does cust. contact me without phone #listed

my advice to you is to take your automobile to your local shop and a qualified technician should be able to diagnose the malfunctioning phone system

Go to your CarGurus.com ACCOUNT (right upper corner web browser) click on Account, then see if there's anything in your inbox dude. Easy as pie.

If u trying to sell vehicle it is best to list your phone number because most viewers are not cargurus members and will NOT use their in- house message service so you'll never see an inbox entry. They will use your phone number but you could also get trash calls. Best luck