Hello, this is the OP. Thank you for your replies, but syntax was the least of the worry for me. I know the sentense itself isn't very idiomatical, but I am more concerned about whether an article a or an can be allocated between 'by' and 'taxi', when we know fully well articles are not used when referred to as means of achievements, such as transportation. I could have easily asked "Is 'Woman robbed at a knife point' correct?" and the logic would still have stayed the same. This was actually a question from a student and we, among the staffs, had a bit of debate on this question, so I was forwarding the same question here, so I would be grateful if by is kept as is, as that is very important to the context of this question, thank you.
'I went home by taxi.' <-- no problem
'I went home by a stolen car.' <-- again, no problem, although it will no longer mean as a method of transportation.
'I went home by a taxi.' <-- This is what I'm wondering about. Many grammar texts mention an article must not be in place, and I need a confirmation! lol