Hello, I am new to this forum. I have a 1991 Chevy S10 Blazer around 160 thousand miles. The engine is a 4.3L its automatic. Today when I wrote it has a miss when I pull a hill it pulls down like it is shutting off the gas but only on inclines and it only does it for a few miles then it will stop it may not do it again for weeks. It sits still and runs smoothly what could it be could it be a sensor getting wet or going bad. Someone said maybe an Oxygen sensor is that it any help would be great.

 

Is the check engine light on?

 

It could be a number of possible things. Oxygen sensors could be it but they have other problems when they go. Could be MAP sensor as you are putting a strain on the motor. Could be TPS sensor which would bog the tranny down. It could even be the mere fact of the incline is making two spark plug wires touch causeing a crossfire(happened to me). Your going to have to poke around under the hood with a DMM to get more info.

 

No the check engine light isn't on