That’s pretty weird! Yeah mine was running reasonably too- much better now though. It had NGKs in previously, and just fitted a new set.I had a 02 like that previous owner didn't tighten up plug 1 and 2 and no2 was soo loose it burnt the coil , and the electrode fell off then plug ,somehow it still ran well?
dunno why but I've had problems with Bosch plugs in coil packs specially in cold starts, cold weather, and short journeys ,
Sent from my iPhone using Tapatalk