Catalytic converters help!

[Wlroberson]

I have a 2011 Infiniti QX56. After I purchased the car the engine light came on for catalytic converters. I have driven it for 2 1/2 years with no problem with the light still on. I had a misfire one day and took it to my mechanic. He said that I was overdue for an oil change so try that first bc it could be causing my car to run rough. I decided to have the cats fixed which was replacing front 2 and cutting and straight pipe the back 2. After 7 days of driving now my car will turn on and idle fine but when I put in gear it jumps skips and runs rough and engine light blinking. Please need some direction! Thanks!

 

[primov8]

A local auto parts store and their pocket scanner should be able to read what DTC(s) is being triggered. The CEL blinking indicates multiple misfires so it’ll likely be a P0300 and possibly other DTCs.

 

[pjdavep]

Your coil packs are probably going, which is bad because if you are sending unfired fuel down to your cats, you are ruining them. Blinking CEL = BAD and you should avoid driving it if possible. You may also be up for the plugs being changed out. If it's been a while, I'd change those out at the same time of changing the coil packs.