Vehicle bought recently has 246k miles. Have extensive records but may never have had spark plugs replaced as there is no evidence in the records. I plan to replace the plugs. Is there any special procedure, etc in order to avoid issues while removing the plugs? Anyone have a problem removing plugs with over 200k miles on them and/or old age (19 years, if original)???

Thanks in advance.

 

You can try measuring the gap on the plugs if interested, but I'd say just replace the plugs. Use the NGKs recommended for your car.

Just try loosening them with a deep 6-point socket. I think they are 14 mm, but test the right socket size on the new plugs. If you find any stuck, then you may have to put a few mL of oil into the spark plug tube and allow the threads to soak. A weaker impact gun would help if stuck, but I've always had success using a wrench, the appropriate sized deeps socket with an extension.