Questions & Answers about Jeg vasker bilen igjen.
By default, adverbs like igjen come after the object in a main clause: Jeg vasker bilen igjen.
You can front it for emphasis (still obeying V2):
• Igjen vasker jeg bilen. (“Again, I’m washing the car.”)
But you wouldn’t say Jeg igjen vasker bilen, because the adverb can’t simply sit between subject and verb in Norwegian.
In Norwegian, the definite article (“the”) is suffixed to the noun.
• en bil = a car
• bilen = the car
Here you talk about a specific car, so you use bilen.