your alternator may not be charging the battery the way it should, go to autozone and have them check your alternator: i believe its free
tune ups consists of MORE than plugs!…have the plug wires been replaced? distributor cap? rotor? fuel and air filter? Pcv valve?
By chance, I heard a similar complaint on the Pat Goss auto repair call-in show this weekend. I believe it was a Toyota Corolla with similar symptoms. His answer was that it might be the lower fuel injector leaking in the central fuel injection throttle body on some Toyotas. However, your car may have multipoint rather than central body fuel injection. Pat said that it’s a common problem that the lower of the two central body fuel injectors is leaking which causes a very rich, hard starting condition. The owner also smelled gasoline vapors inside the car on some occasions. If this is the case, then it should help to hold your accelerator pedal all the way to the floor when cranking the engine. That forces your throttle plate to be wide open which lets as much air as possible into the fuel mixture. It also tells your ECM computer to stop injecting more gasoline into the engine. It’s the “clear flood” mode common to most cars whether they’re the old carbureted or the new fuel injected type.
You want to replace not only the plugs, but also the, plug wires, distributor cap, air filter. But to be honest, it sounds like your problem is in your starter. The starter itself could be going bad and quite able to turn as fast as it used to. A reputable shop will have the equipment to hook up to it and see how much juice its pulling when it tries to start, this, as well as listening to it start will help them acess whats wrong with it.
Most shops charge a diagnositc fee of about $50, this is usually waived if you have the work done there. My advice, find a shop that displays an ASE certification and ask them. Dont ask them just to test the starter, tell them whats wrong, they will know what to check, and they will be able to determine if it is the starter or not. Hope this helps.
Here is the link to the Better Business Bureau, if you dont have a trusted repair shop you use, this site can help you find a good one.
it could be the starter dragging.craw under your car and see if the starter is tight.