91 chevy 1500 stalling and chugging

i have a 91 silverado 5.7
i just had a new fuel pump put in and filter so i know it isnt with that part of it
but some times it will run fine then 20minutes later start chugging and wanna stall , it will idle usually but when i hit it act like it stalled then when i let off still idle, some times though it happens right away goes back on forth and how long it takes to happen, and last night i went for a ride and it stalled on me and took about a good 10minutes to get restarted
i know it was getting , didnt check spark last ngiht though
but i went and put on a new rotor and cap and spark plugs and wires it needed it ne way but i hoped it would help alil but no still doing it
i tried a new map sensor and nothign changed.
also when this happens the check engine light will come on but once it stops the light goes off so i havent had a chance to be abletoscan the truck with the light on still
ne one have ne ideas

Hi Moparman,
This sounds like the same trouble I have with my -89 k1500.
I still don't know what is causing this, but keep an eye on my thread as well. Maby we have the same problem?
I'am going to check my EGR-valve tomorrow as suggested by Bob and well see.
Good Luck Man!

Hi Moparman,
This sounds like the same trouble I have with my -89 k1500.
I still don't know what is causing this, but keep an eye on my thread as well. Maby we have the same problem?
I'am going to check my EGR-valve tomorrow as suggested by Bob and well see.
Good Luck Man!

well i did wat my mechanic said i disconnected the map sensor and it ran and made it for a lil ride
my screen name for aim is moparman48081
yahoo is streetracer72dart
hit me up on one of those and we can talk about this and see if we both do have the smae problem
josh