Lost ground to under dashboard

seems wierd my 88 xj did not want to start and i chased down to no groung to lower dash ,BUT, the upper dash had ground!!!!!!!!!!!so i jumped a new ground wire from the upper dash to the lower dash and my xj started to run again.Well here is where it get funny-my jeep did not want to start today and i checked everything-i am a master ase cert tech for 18 years now-it seems that the ground was lost for the sensor grounds which are provided by the ecm has been lost -sssooooo i added my own ground there. now when it runs it is ok but when i shut it off and try to restart it it wont i must let it cool down for a little for it to run again.an my crank sensor ohms out to around 262 or so.what the hell is up with ground issues on the @$%@^#!@%@#$^@^#$@%^@#$^!@$% renix french bs!!!!:gonnablow

what about the ground on the back f the head. Everything grounds through that strap on the Renix.

cleaned it plus i have a seperate ground that i added from the battery to the body at the battery i have clened all ground xept fer the one under the kick panel- uh i did not find any there so maybe the fault could be there??????? man i tell ya it makes me want to get a pcm and wiring harness from a gm like mid to early 90s 3.8 liter and wire the whole pcm and harness to have my jeep run RENIX FREE!!!!!!!!!!!!!!!!either that or my jeep is jinxed for good by the french gremlins!!!:shiver: