I have two 98's . One of them has always sailed right through and the other has been finicky. Two years in a row right after Ga took on OBD testing I had to get waivers because the state software wouldn't accept a lack of a code as no code set. "Not ready" was a pain in the jerk for me. Volvo was worthless when I went to them . They gave me a list of driving stunts to do that would help it get "ready", but when those failed, they said I just had to drive the car for awhile to get it "ready" . I reset the ECU and drove it for almost two weeks before it was ready again. During those two years the state finally fixed their software to allow S70's to pass. As I stated, my S70T5 never even brought about a hiccup from the machine, so i 'm dumbfounded as to the difference between the two. Also, since those two years I have had no problem sailing though with either car . Good luck.