Intermittent starting issues?

Have to wonder if it's like my s10. If it sits more the two days it won't start. It cranks, has spark and fuel but won't start. When I let off key it acts like it is dieseling or trying to run backwards for a second or two. Only eat to get it going is to tow start it and don't even take a block to get it going. Then as long as I start it every day at least once it's fine but after two days I can't even jump start it. Oh I have 2 shell drive 1999 s10 4L v6. Live the truck. Felt stupid because I owned it a year before I realized it had 3rd door. The driver side rear opens.

I use to work as mechanic but this one stumps me.I went to start it one day after it set for about 4 days. It would crank, has spark and I can hear fuel pump butt it won't start.I can wear battery down and then jump it and it won't fire.I had to move rig so I got tow and I put it in second gear and it fired up. If I start it every day it's fine but after two days I have to get a tow to start. Im going to add something here but reluctantly. After this issue started I misplaced key and had to move rig or get towed so I drilled out ignition carefully. Then found key but loose fitting it would trip security so I bypassed it by cutting one of the four wires at key and splicing it into the other wire to bypass it then did key relearn. My security light stays on all the time but ass long as I start it daily it's fine.I only mention that to rule out the security key issue.I plan on replacing key lock and using my old key by changing tumblers and relearn old key after repairing the bypass.I can't afford to do guess and check by buying random parts. My thought is ignition module because I know there is two parts to that. Once it reaches about 500 rpm the computer takes over and tells it when to fire.I had a 1994 c10 that when it got warm it would die and not start until engine cooled off. It wasn't overheating just bad modual.I have the 4L v6 I think it's 4.2 but can't confirm that. Know I should but rig is across town. Had to get a tow start again. Let it set 3 days. What do you think.I use to be on fixed income.I only got paid for what I fixed. Now I don't have income. But that is another issue

I have a 1999 chevy s10 that is a very dependable truck. During the Spring, Summer, and pre-Fall it starts up with not a problem of hesitation. When the temperature drops it will not even startup as you crack on it for more then 30 mins or so. Since it is a manual transmission you can roll it off a hill at our place and it will start up right away. I took a blow dryer and placed it on the coil pack from the bottom of the truck and let it run for about 5 mins with key turned on. It starts right up. I thought it was the coil pack and replaced it with a new one and still getting the same problem on not starting. Also, when I came home it has started to die and jerk and I try to restart it while in motion on the road with it in neutral. It sometimes hits and starts right up. It will not work when your in a gear trying to start it. This has happen about three times with many weeks apart traveled about 25 to 30 miles distance. They aren't no codes present or even when it dies during transit. Where should I put my focus at on this and how should I do it?

This is what my truck is doing. It will start every day just fine but let it sit two and I have to get a tow to start. Fuel pump is running and has spark but did notice that when it acts up and I try to start, as soon as I let off key it diesels about 1.5 seconds like it has jumped time but once start try credits fine until it sits couple days

I will try to keep it simple. If it sits more then two days it will crank and when I let off key it diesels for 1.5 seconds. Can wear down battery trying but only way it starts is if I tow start. It starts quick and once running I cann shut it off and it will start back up. Only after about two days of not running will it act up.