Good Morning, I have a brand new Ford Transit 350 Hightop that has been converted to a Mobile Pet Grooming van. It has a Cummins Onan RVQG500 (gas) 5.5HGJAB-1038L generator, also brand new.The van has 750 miles on it and the generator 20 hours. After grooming the pets at one stop and turning off the generator and then starting the van and driving to the next stop there is a smell of gas in the cab of the van only. Not in the salon where the grooming takes place. Not in the closed off back section where the equipment, generator, water tanks are. The smell only happens after the generator has been on and shut off after grooming and when she drives away. The smell gets worse during the day if more than one pet is groomed. It has made her have a bad headache as well as throwing up. It is a gas smell not exhaust. Does anyone have any ideas what could be causing this. Have taken it to Ford and have dropped it off at a Cummins Onan Registered Repair but he has not got back to me. Help. Thank you.