Sluggish excelleration

older model S10 pick up, started getting sluggish when excellerating. seems to get worse as you reach 30 mph

actually worse now, barely able to climb hills…cat convert comes to mind? firsh thought was vaccumn leaks…found a couple, slight difference

To check for a plugged up cat, put your hand by the exhaust pipe end when it is idling, if you can feel the individual bursts of exhaust, that is not the problem. If it is a smooth stream of exhaust gas, there is an obstruction.

You may have low fuel pressure or dirty fuel injectors, or any number of other problems that would probably require a professional to identify, so start with the easy stuff…

More common problem on older cars is weak spark causing a misfire during acceleration. Does the car seem to sputter a little when accelerating? Start by unplugging and checking for corrosion in the connectors in all the low voltage wires in the ignition circuits.

Look under the distributor cap - are there what look like pencil lines across the plastic? Those are microscopic cracks that the spark is following, rather than going where it is supposed to. If it is old, replace cap and rotor.

How old are the spark plug wires? More than 10 years old? When in doubt, replace them with brand name wires.

How old are the plugs? More than 20k miles on conventional plugs, or more than 50k miles on platinum plugs? If so, replace them with correct plugs for your vehicle.

Not an issue for your car, but if you are ever buying plugs for a late-model vehicle, don’t have absolute confidence in every reference you see regarding the correct parts. A number of years ago, AutoZone sold me the wrong plugs for a RAV4, and it ran really badly until I figured out what the problem was and changed them. I was really surprised how much difference the wrong plugs made, even when the vehicle was cold. The plugs looked similar in dimension to the correct plugs. When I went back to AutoZone, they double checked their computer and said that the plugs were correct. They refused to believe that their computer system could be wrong, even when I showed them another reference that disagreed with it.

Besides all that Manolito said, a simple thing to check/change is the fuel filter (IF it is external to your gas tank; I don’t know), especially if the present one has been there a long time/miles. Old clogged filter will cause fuel starvation, whose symptoms are like what you describe.

(I learned this one from personal experience.)

Afterthought - ‘old’ S10, how old? Is that an early HEI ignition? If so, look for gray or brown burned spots on the coil housing in the distributor cap and around the center of the rotor where spark may be shooting though. If found, replace the cap and rotor and the spark plug wires.

it is a 96 model

this is a good suggestion. my son runs on fumes quite often…could have drawn some ggunk from the bottom of the tank

Just stand at the back of the vehicle and have someone floor the gas pedal, it’ll be obvious if it’s plugged. The place I would look at is the fuel delivery system. You might have plenty of pressure but, lack fuel volume. I’ve seen this a lot on older vehicles.