1999 rodeo 3.2L ck. eng. light on p0103,p0104 MAF voltage high and low also p0401 insuffient EGR flow vehicle will die randomly. Have snap on scan tool can not self test unless I hold key over to start position. But other scan tools will work on vehicle. Has had MAF replaced 2 times. I replaced ing. switch thinking it would let me self test still unable to self test. While holding the key to start position monitored data loses voltage to MAF and usually bucks or sometimes dies when losing signal. Maybe I have a glitch in software on scantool but works on everything else. Could someone help me.