Having a problem with my 2002 Pontiac Grand Am that seems to have all the mechanics I’ve taken it to baffled. Car starts great in the morning. I can drive it around, then park and come back 30 - 60 minutes later, it will not start. It sounds like it is going to start up never the engine does not completely engage. If I wait anywhere from 30 to 50 minutes it will start. It use to happen only mid to late afternoon but now that the weather is getting hotter, the problem is occuring earlier each day. Battery, starter and alternator check out. One mechanic thought it was the crank sensor which was replaced and the car worked great for about a week then started not starting again. And, of course, it never acts up when it is in the shop. And suggestions. When it runs, it is a great driving car for its age and having almost 200,000 miles.
Ok, you need 2 things for any vehicle to start… fuel and spark. An easy way to see if you are getting a spark is to disconnect one of the plug wires at the sparkplug, get a nice long screwdriver, insert it gently into the boot at the end of the plug wire, and then lay the screwdriver close to but not touching an unpainted metal surface. Then have someone crank the car and see if you get a spark jumping to the metal from the screwdriver. If so, then suspect a fuel problem. If not, start suspecting things like bad plug wires, a bad coil pack, or a bad crank sensor…even if you just had it replaced. new parts aren’t always good parts.
fuel problems are a bit trickier to diagnose. Best left to someone who has the proper equipment and knows what the fuel pressure should be.
to me it sounds like either a bad fuel pump or a bad coil pack ( coil packs are how newer cars make a spark to send to the plugs).
i had the same problem with my gran Am change spark cover crank shaft sensor and worked for a bit then the problem started again so guess what i sold it problem solved.