Possible Solution to Astro Van 97, 98, 99 Starting Problem. If you have the following symptoms, this may apply to you.
-For years my 98 Astro Van had trouble starting in 'cold or wet weather', or damp weather, especially when there was fog, or heavy morning dew. Otherwise it would start fine when it was dry, even when it was freezing (as long as it was dry). Sometimes I would run the battery completely down and need to recharge before it would start. It would turn over great. I could hear the fuel pump 'hum' properly. Once started, it would run fairly well. However, if the truck was parked for more than 20 hours, in the damp weather, it would not start again. I changed may things including distributer cap and rotor, cables, plugs, fuel filter, etc... with no effect. And then I one day I noticed the problem. The ignition coil!!! A $70 part!! Basically, the coil had a small-crack in the case. When attempting to start, a large spark about 1" to 1.5" from the coil would short to the coil frame. Electrically it makes perfect sense! The electricity would much rather short to ground(less resistance), than continue on its way through the distributer, and on to the plugs (more resistance). Also, when it is 'wet or damp' the short has an easy low resistance path, but when it is dry, it is too hard to short, and so power flows to the distributer, and your van starts.
-->It is really easy to check for yourself. Just remove the engine access panel inside your van. Locate the ignition coil. Turn the start key (especially when it won't start) and just look and listen to the ignition coil. First make sure all the wires on the coil are properly and firmly connected. If you see a large spark or hear the clear crackling of electricity, you have found your problem. The van starts great now, within less than a second, every time, no matter the weather. I changed my coil myself, but it is a bit hard to reach. I noticed that the replacement coil is 're-designed' and has a heaftier plastic mold around where the original crack was on my factory coil. I have read through most of the posts on this site and others, but in the ones with these symptoms, it seems most people overlook the ignition coil. Good luck and Post back if it works for you too