20 Most Recent 1993 Chevrolet K1500 - Page 8 Questions & Answers

41 indicates Rpm sensor, at left front wheel, 42, is right front sensor. I'd check for dirt in and around both, clean connections, and wire brush or whatever the toothed ring to clean it all up, then clear codes & see what happens.

Borrow a repair manual for it from the libarry to guide you though it,

Your thermostate is probably stuck open

usually these are under the hood it is a small black or green box