It may be an obvious question but how do you know it's the lens that is blurry. If your vision is blurry it could be due to other ocular complications which need to be investigated.
A few questions for you to think about and answer.
Is this a gradual blurring of your vision? - A common complication of cataract surgery is capsular opacification which is a hazing of the capsule that holds the implant in place. However this could also be other pathology such as dry age related macula degeneration and needs to be investigated. To be honest it could be one of many things but assuming you are of a certain age due to cataract surgery dry amd is high on the list of probable causes. It could be a change in your prescription but this is less common following cataract surgery.
Is this a sudden blurring that you have noticed? - As sqad suggested the implant could be dislocated but this is less common now and would be mainly associated with a head trauma. It could also be something like wet macula degeneration or a bleed at the back of your eye related to hypertension or diabetes.
With wet macula degeneration you may notice significant central distortion (look at a window frame and see if the lines are straight or distorted in any way). THIS NEEDS TO BE INVESTIGATED ASAP (GO TO YOUR LOCAL HOSPITAL EYE CLINIC OR A&E) IF YOU NOTICE THIS AS TREATMENT WORKS BEST IF EARLY.
You should book an eye examination with your local optometrist who will referral pathways available depending on what they find. At this appointment they may put drops in your eyes to assess them more clearly so you may not be able to drive immediately after this appoinment.
Hope this helps Let us know how you get on