1984 S-10 PU runs rough (intermittent)

[stanb5]

My 1984 S-10 Pickup, 2.8 V-6, 173,000. Good compression, recently replaced plug wires and plugs and rebuilt carb. Usually runs very good, almost like new. Occasionally, power is reduced and much vibration is felt in the steering wheel and lasts for 5-10 minutes. Could this be a failing catalytic converter and how do I check this. What else is likely to be the cause? Any help will be greatly appreciated.

[bejay]

most any exhuast shop should be able to do an exhuast backpressure test and determine the condition of the catylitic convertor however they are usually do not cuase an intermittant problem and likely not the cuase of your problem.