I have a 95 Blazer LT. 2WD v6 4.3. no codes but idles hi & when I come to a stop it idles rough , It feels like it might stall if I put it in nuteral it's not as bad. I've changed the ignition module I put new plugs and wires replace the fuel injectors the spider and the distributor was checked and is good . Any advice would be appreciated

 

is that 4-3 TBI or EFI? my 89 and 91 long box S10s had vacuum lines all over the place to the TBI and ran like crap once they started breaking. and I couldn't find them all and eventually had to junk the one that had zero power at all. then the other one dropped a drive shaft and pole vaulted it into the rear diff so that one went to the junk too. that my friend was not a fun ride at 50mph.

 

Like Bravo99 said, you may need to check your vacuum lines. A good way to do this is to spray little spurts of brake cleaner in areas to see if the engine revs up a little bit. Sometimes this doesn't work but usually it does. If it doesn't do anything a vacuum line could be collapsed in on itself. To check that I would just gentle squeeze the vacuum lines to see if they are soft (can be done with or without engine running). If you know anyone with a good scan tool that can read data values, then I would look into the TPS (Throttle Position Sensor) and the IAC Valve (Idle Air Control Valve). These two items can cause a rough or high idle without setting any codes.

If the engine returns to normal operating speeds and doesn't have an issue with the idle while in park or neutral, I would also look into the transmission pressures and torque converter lock up values. If the torque converter is starting to go bad it will cause a rough idle in gear and when it goes bad, the engine will stall when put into gear. If the idle is rough or high in any gear I would highly doubt the torque converter is your issue.