The potential fault centres on a damaged seal that may have been fitted to the secondary bulkhead in the engine bay.
The carmaker notes that a fire could result if the seal were to come loose and make contact with hot engine components.
The seven affected vehicles were sold between April 1 and May 1 of this year, and Mercedes-Benz has confirmed it will write to owners for an inspection to be arranged.
Mercedes-Benz has sold 737 E-Class models in Australia, year-to-date (end of July, August figures still to come), compared to 914 for the same period in 2014. The coupe-like CLS boasts 289 sales for the year, which is up on 257 at this time last year.
An all-new E-Class has been spied in recent months and is expected to debut in the very near future. A new CLS is still to be confirmed, although it understood the carmaker has ruled out a new Shooting Brake variant.
This latest recall follows one announced in August for the small A- and B-Class models, which focused on a potential fuse-box fault.