You need to contact the claims adjuster and say there is mechanical damage.
Try ONE phone call and if you do not hear....Sure take it to a mechanic and get an evaluation....then I would ONLY communicate via emails. You need to keep a paper trail. They want to talk so they can stall and delay then 4 months from now,, "Wow, its been four months, you needed to do something sooner, we have to deny your claim as this has been too long."
You simply state, "The vehicle has suffered mechanical damage and needs the be evaluated by a mechanic. Please re-open my claim and inform me of what steps you would like me to take. Please reply within 3 business days. Thanks"
If this does not work, then ask for the claims adjusters manager, be polite, but direct. And do not threaten to sue or make false claims, just that this is not working out and you need it elevated to a manager.
If that does not work you will need to get a PAID evaluation from a reliable dealer or shop. You need to pay them as having the mechanic guess, or say it could be one of 5 different things will not work. You will need a specific quote for the issue and needed repairs.
Then you need to write a letter and send via certified mail to the Ombudsmans office of the insurance company. DO NOT tell the adjusters you are going to do this. Then follow up in a few days with a phone call. Keep any calls short and to the point.
If that fails file a written compliant with the state office that regulates insurance companies. AGAIN, in writing, keep copies of all letters, if they have a form fill it out and send it in with a short letter.
Best of luck.