I have a 1990 Chevy Silverado that recently started backfiring every once in a while and seemed to be struggling for gas at the same time-sounded like it was skipping (usually when going uphill). Only did it every once in a while. Changed the fuel filter and it stopped. It has started back only worse. Changed the fuel filter and it did not help this time. Now it won't stay cranked. You can crank it up, but you have to keep stomping on the gas (it doesn't rev up) and when you let go of the gas it dies. Any ideas of what this might be????? I could use all the advice you might have.

 

Check fuel pressure. It may be a bad fuel pump.

 

Yeah rule out fuel problems before you start replacing parts.