My Chevy Blazer 2000 doesn’t have strength when I put it in D. If I change it to third, second, first or R it does run well. Could someone give me an idea of what this problem could be?

 

By not have strength, what do you mean? Does it go into gear at all when you select D? If it drives and shifts fine in other gears, maybe your shift cable has stretched? I had that problem, but mine never would go into park.

 

Neutral safety switch cable I think???

 

when it is in D it does not run, only when I change it to another gear.

 

 

If I switch to 2, 3 or R it continues to work very well. If I switch it back to D and press the pedal no power.

 

Have someone in the truck moving the shifter from park down through the gears, while you lay underneath and watch the shift linkage. Sounds like it's not going into drive and getting lost in some neutral position