Oh, no. Everyone at the dealership was saying it wouldn't have high enough backpressure and would get my engine check light but I haven't had this problem, then they said give it a while. I have done exhaust work to several vehicles and had experience around a fair amount of vehicles to know what to expect. I do feel the weld job needs to be checked because it almost sounds like a rattle when I open it up too quickly. I will make sure to check this first opportunity today.^ hahahaha..... without the resonator does your car throw any codes or is their a fix for that (as you can tell I don't know much about this hence the dumb question)
I don't expect any problem with backpressure unless you run without a muffler, shorten the pipe to the rear axle and run it catless without the resonator and you MIGHT have an issue with backpressure then.