Last yr 9/2018 -my Honda 2012 rough idling - engine light on. Replaced all spark plugs with a mechanic. Last Saturday 11/16/19 first time again it started rough idling - engine light started flashing. The other mechanic shop I drove to who replaced spark plugs was closed on Saturdays, so I took to Galaxy first time. On Monday morning, George called, said I could replace all spark plugs, 3 coils that were bad for $750 - & add a throttle clean $89 around $850 or he recommended $1,220 to replace all spark plugs, 6 coils (said 3 of the 6 were bad) and clean throttle. I told him that I had verified with the other mechanic that all spark plugs had been replaced last year, and he said he didn't think the spark plugs had been replaced, since he didn't see signs that it had where it leaves little indentions when replacing. My finances are very tight, and my son & I went and told Galaxy that my son was going to help me. I had called my son in tears about my financial situation - and he decided to help do the tune up with a friend mechanic. First off, that mechanic asked for the VIN number on my car. He said there was a TSB (service board) on my car about the engine "missing", on my Honda 2012! It had 8 years limitation for repair, with no mileage limit on that repair. He explained that oil would be leaking in there to spark plugs due to the engine problem. I got him the invoices that showed I'd replaced the spark plugs 9/2018, and he had to upgrade the PSM I think it was called - computer in the car - cost $250 which I did have to cover. Then he told me, if it happens again - you have proof the car computer was updated, and that spark plugs were replaced, go straight to Honda and they should repair for free!!! And that my coils were ok. So, I picked my car up 11/20 and have driven it fine until yesterday 11/24 when the engine light began to flash and the rough idling started. Tomball Honda service dept is open 7 days week - so at 5:00 p.m. I drove my car up there and explained there was a TSB on my car for "missing" and I've replaced spark plugs last year, here's the invoices, and invoice for computer update - please check it out. Well, Jozef came to me after Honda technician checked it out last night and said, the spark plugs had gone bad, because of the TSB engine missing issue, where the oil is getting in there due to this engine TSB missing problem, and that is exactly what the friend of my son explained to me. Tomball Honda gave me a free loaner car last night and is repairing my car for free, with new spark plugs. Make sure sometimes it could be a more in depth problem that first appears and check for any recalls beyond safety recalls.