One problem related to ignition module has been reported for the 2004 Chevrolet Classic. The most recently reported issues are listed below.
I own a 2004 Chevrolet malibu Classic. For the past year or more I've been having problems starting my car and the only resolution is to wait 10min. With the ignition in the on position until the theft system light goes off. I figured this out by reading the owners manual but I feel sorry for the many folks who spent hundreds of dollars before doing so. It was only happening every couple of months and has progressed to happening 1-2 times a day. The theft light will now even come on at times while driving. I'm just afraid the car might shut off while driving and cause an accident. The gm dealer says it's probably the ignition cylinder or the body control module that need replaced. From what I've read on the internet forums that has not fixed the problem. The problem resides in the passlock security system and the only way to remedy it is to have it disabled or bypassed, but not by gm of course because they won't admit to the problem. Since gm won't fix the problem, there should be a recall that will force them to. I challenge you to read the forums for yourself on this issue. I feel the evidence is compelling as I expect you will also. Someone needs to step in and take control on this one and I'm afraid that you are the only one who can. Americans are struggling to afford driving with fuel at $4. 00/gal let alone being deceived by gm into spending hundreds of dollars for unjustly repairs. Thank you for listening.