so i just finished an alternator and power steering pump changeout, coolant and oil change, serpentine belt and general engine check/clean. Put everything back and am getting a range of rpm's from about 1000 to 500, very predictable...up and down with a little engine roughness. (tach doesnt work so this is a guess). Prior to working on it I blew it off (gently) to get the grease off. No codes, changeout went good, still no codes so i am currently stumped. The only thing i may have screwed up was reconnecting the two small hoses from the PS pump back to the intake and engine but I reversed to check and no diff.
All I have learned about the above work I learned from this forum so thanks, also searched for this issue but cant find anything. LS400 is a 92, has 127K. Thanks for any help, this is a great forum.