So I’m new to the dsm scene, I’ve done boost leak test and none, has new cas, and cps..battery tested good, alt tested good, new plugs (7’s) gapped at .28. So here’s my issue, sometimes car runs great and sometimes it will start fine take off fine but about 5 or so minutes into driving and rpms will jump around, check engine light pops up, battery light, sometimes air bag light..I thought I was having a battery issue or alt but both tested fine..it’s becoming to be a huge headache could someone maybe give me some pointers on what to look at? I’m starting to think maybe ecu issues? I figured if it was coil pack it would be a constant issue but it’s not every time I drive the car is does it just randomly bit more often here recently! Now I’ve only had the car bout 2 months and haven’t driven it much! Ran great on the way home besides hitting fuel cut, I took off mbc and routed line from wg to the jpipe, recirculated the bov like everyone was telling me..that’s all I’ve done since getting it. Today I went to drive it and I got about 5 min down the road and i I noticed my wideband and boost gauge lost power and noticed my rpms were dropping to 0 then coming back to 2500k multiple times, then car died and wouldn’t fire up, then key on all lights come on but soon as I try to crank it acts like battery is weak...anybody have any idea??

Check your engine wiring harness...

Check battery connections including grounds. It sounds like it’s losing connection. Some batteries will test good until they’re warm or under a load.