89 blazer backfiring, high idle

[westcoastfball]

It has a crate 350, and it just started back firing on me today and also theres hesitation when i accelrate. very high idle when i come to stops, please guys i need help to fix my baby!

 

[Dabba]

vacuum problem?

 

[buffblazer]

It has a crate 350, and it just started back firing on me today and also theres hesitation when i accelrate. very high idle when i come to stops, please guys i need help to fix my baby!

check your timing

and like Dabba said check your vacuum