Engine sluggish, loses power and smokes, sometimes backfires

1997 MITSUBISHI TRUCK
72,000 MILES • 3.0L • 4 CYL • 4WD • MANUAL
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GORANKURTAGIC
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  • 1 POST
I have an intermittent problem with engine lagging power at the times. Randomly but mostly when decelerating and not all the time. What happens is that the engine becomes sluggish, loses power and smokes, sometimes backfires until I let go off the pedal and change gears. The. The power slowly returns but sometimes it takes a bit longer. Could it be possible that the engine exhaust brake could in the the stuck/closed position preventing the truck from reaching its full power and causing the symptoms as described?
Dec 30, 2018 at 1:00 AM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
It does sound like you have a clogged catalytic converter. But to be sure here is a guide to help confirm the issue:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please run down this guide and report back.
Dec 31, 2018 at 11:28 AM
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