I own a 2012 chevy silverado Lt 180000 miles and the other day it just went into neutral. Had towed home . It starts fine goes into gear now fine but gas gauges keeps changing level (from a 1/4 tank to full) and haven't drove it and now it tells.me no oil pressure which it has oil... getting ready to put on a live scanner ... any thought would b greatly appreciated .... only codes I get are 7E8 , 7EA , 7EB. Researched them... but it jumping all over with electrical has me stumped... all suggestions greatly appreciated