94 isuzu truck idles high, then tries not to idle at all. has moods

Question

it's a 2.3 carbureted, And it DOES pull a"CHECK ENG" light, but when I check it through the OBD 1 port, it has apparently no trouble codes stored. Auto how can ECM not store the code(s)? Could it be bad? How would I know? Thanx much in advance.....

Answer 1

Could be the EGR valve sticking, or as is the case with my 95 Rodeo, the linkage sticks, I spray it with WD 40 and it is good for about a year