1990 Ford F-150 — catalyst efficiency code but car drives normally

Log the conditions before you spend. Loaded-suspension checks on the 1990 Ford F-150 catch play that a wheels-hanging inspection misses. You'll know quickly if you're on the wrong tree. On “150 — catalyst efficiency code but car,” that was the fork that mattered for me. Verbal 'we'll take care of it' is not a plan. Climate here is different, so treat that as a local data point. I'll update if anything new shows up.

OP update: scanned the 1990 Ford F-150 again and still only have the one pending code, no new lights. Not driving it hard until I know more.

I'd want a measurement, not a hunch. Swap the cheap/easy piece first on the 1990 Ford F-150 and see if the fault moves. Save the big job until that test fails. I'd want that in writing, not as a promise. I'd sleep better after that step, even if it finds nothing. Video is ugly but it shows the hesitation.