2002 Chevy Malibu

My car will start in the morning but not in

the heat of the day. I’ve taken it to the

dealer twice and their diagnostics reveal

nothing. The ignition is hard to operate but they have discounted that. Could it be

the ignition or possibly the spark plugs.

They have over 90,000 miles on them.

“The ignition is hard to operate” Do you mean that when you try to turn the key in the ignition it is difficult to move? Do you have a lot of keys on your key ring?

What exactly happens and does not happen when you try to start it when it is hot?  Are you able to turn the key?  When you turn the key does the starter turn the engine and if so, does it sound the same as when it is cool?  

If you have the original plugs and wires, it certainly is time to replace them, even if they are not yet causing a starting problem. I would add things like air cleaner oil and oil filter could also be far past due.