at what milage should a person change the spark plugs on a 2001 Grand Am GT? fuel filter? airl filter?

dealer sales people and manuf. tell to sell, under very easy driving conditions spark plugs can last 90k but you risk the spark plug siezing to the aluminium cyl head, then it realy can become expensive . if changed at 60k to 70k siezing has not been a problem. air filters depend on where you liveand how you drive but around 30k most filters are completly blocked. fuel filters, 15k seems reasonable now that e-85 fuel is being pushed fuel filters will suffer and may not last 10k on older cars [the ethanol picks up scale scum and any other crap inside the tank cleaning it out,once clean it will be ok]15k is good but expect increased life after continued use.

As long as the vehicle still has the platinum spark plug like it did from the factory Plugs are good in most cases to 100,000 miles that is the factory recommendation and by that time if they aren't worn out they will be getting close to being worn out. Fuel filter should be replace at 30,000 miles while it may still be ok it should be replaced otherwise it could leave you sitting when it goes bad. With the air filter the mileage that it will last depends on the type of roads you are driving on if you regularly drive on gravel it gets dirty faster my recommendation is to periodically remove and inspect it if it is looking dirty replace it.

Use the K&N re-usable air filters, about $40 but, you never have to buy another air filter again (pays for itself), just clean with a hose, and re-use, flows better dirty, than paper filters when they are new. This adds a few more oats under the hood (engines are basically air pumps), it will NOT void any warrantee issues on the car either. They fit right into the stock factory housing on the cars filter (exact replacement, only BETTER ! They use these filters on military helicopters in the Desert, so they must be good ! K&N engineering co.

80,000 miles on the plugs and fuel filter, and 23,000 on the air filter, all assuming typical operating conditions.

GM may say different, but these mileages work for me on modern cars when all things are considered.

Pull the plug wires off the coils one after the other and look for rust/corrosion on the coil terminals, use coarse sand paper to scrub them up. verify for oil leaks on the intake manifold. that is someone-friendly issue on 3.a million liter autos for the intake manifold to leak oil and coolant. look for any cracked vacuum hoses. whilst that is dark look on the motor on an identical time as that is working and look for any arcing around the coils,plug wires,and so on. a undesirable gas injector will additionally reason misfires. verify the resistance of each injector with an ohm meter after removing the harness connector. they must all learn the comparable resistance.