I work for a university where students are often approved for a Sallie Mae loan, but usually only for a small amount (less than $2,000). When the amount gets higher, then factors like income and the length of your credit history will matter more.
Getting Started. Fouled, damaged, or worn out spark plugs can lead to a variety of engine problems, such as misfires, hard starts, increased emissions, and poor fuel economy. For most vehicles, you should replace your spark plugs every 30,000 miles (consult your owner's manual for your specific interval). It is also recommended that you replace your spark plugs wires at the same time, or you may still experience misfires or other problems.
Spark plugs last a long time but they donât last forever. Most spark plugs have a factory service interval of 100,000 miles, though some may be as much as 120,000 miles. Long-life platinum and iridium spark plugs will typically last up to 100,000 miles or longer provided the engine isnât using oil or doesnât spend a lot of time idling. Replacing spark plugs at 100,000 miles can be troublesome on some applications.