Unlimited fines given after German carmaker mixed hydrocarbons (7)

I believe the answer is:

benzine

I'm a little stuck... Click here to teach me more about this clue!

'german carmaker mixed hydrocarbons' is the definition.
I can't judge whether this defines the answer.

'unlimited fines given after' is the wordplay.
'unlimited' indicates the central letters (discard the edges or 'limits' of the word).
'given' says to put letters next to each other.
'after' becomes 'benz' (I am not sure about this - if you are sure you should believe this answer much more).
The middle of 'fines' is 'ine'.
'ine' put after 'benz' is 'BENZINE'.

Can you help me to learn more?

(Another definition for benzine that I've seen is " fuel".)

I've seen this clue in The Independent.

Want a hint initially instead of a full solution? Install my app