Need some help for my friend(non tech savvy) before he switches his JB4 for a custom tune.
He explained that his boost levels fluctuate a lot under acceleration. He took me for a ride and I could feel hesitation on map2 so I had him run a few logs. I could see boost drop repeatedly throughout each gear, and really bad when accelerating in 6-8 at low rpm.
The log from lower rpm in 6-8 looks like a heartbeat and boost drops repeatedly while accelerating.
His ran smoothly on map1 until he switched to Denso plugs at .022. Is this misfires from new plugs, or could it be coils? Any tools or way to personally test each plug/coil without re-pulling them? Like old school ignition/voltage testers, but for DI?
I’ll try to get him to send me logs to post since he doesn’t visit forums. But hoping my description will suffice. Any suggestions are greatly appreciated and thanks in advance!