1997 Ford Ranger with cat failures

I have replaced the catalytic converters in my 1997 Ford Ranger twice now and need to have them replaced again. What causes them to fail and how can I prevent it from happening again?

  • high mileage. do you drive a lot of miles every year?
  • engine/cat design. it may be this is just typical of rangers. the 97 ranger came in 3 different engine configurations, which do you have?
  • problem with the fuel/air mixture, have the fuel trims measured.
  • rapid accelerations. difficult for the engine computer to keep the air fuel mixture in its proper range, esp in engines using a map sensor, which I believe is the case for your ranger.
  • rust. do you live where they put salt on the roads in the winter?
  • diagnostic mistake. sometimes a cat will be replaced when the cat isn’t he problem, it’s something else, like a faulty o2 sensor. what is motivating you to replace the cat? doesn’t pass tailpipe emissions? check engine light?

My 26 year old Corolla w/200k miles still has the original cat, and passed the bi-annual emissions test with flying colors recently.

Does your truck burn oil? Too much oil will clog a cat.

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