problems with 87 crx dx

Well I have been having problems with my alternator, I thought it was the wire coming from the alternator to the battery so I ran a wire directly to the battery and for now it is charging it. Since then though my engine idles at 2000 rpms and sometimes when I am driving and come to a stop if I take it out of drive and put it into neutral it will idle up by 3500 rpms for a min and then go down. Then this morning I stopped at the store and I went to start the car it wouldn't start up I figured it was flooded. So I waited and it started up slowly after 20 minutes but sounded rackety for a minute. It then stalled twice driving it but started up right away. Also while I was driving it I noticed that my temperature gauge was all the way up, so I put on the heater all the way and it went down to about half way but as I drive it, it went up and down. Finally as I turned off the engine it kept running for a few seconds and then finally sputtered out. I am not sure what the problem could be I always tried to take good care of it and so far it has never given me problems.

I would take the car down to an automotive shop. I recommend Wal-Mart because they'll usually check your batt/alt./starter N/C. It could be the voltage reg. for the alt that's giving you grief. For the overheating did you check the thermo? Purge air from the system (bleed screw on block)? Is your lower Rad. hose heating up at all going back to the block or does it stay cold? For me it was a combination of a poor circulating water pump, gunked up thermo, and old clogged up rad... Now mine cools like a champ... :P

The sputtering after you turn the car off is due to overheating. It's called detonation and happens because the pistons have developed a hot spot which causes the fuel to continue burning (like a diesel).

Is there white smoke (steam) coming from the tailpipe?