Motor differences

I recently bought a 2013 speed with about 71k miles on it. I brought it home, and within 16 hours of having it, it’s already misfiring. It threw a p0300 code so I just threw in coils and plugs. Seemed to go away for about a week, then it comes back, so I take it to my mechanic who works on speeds. He informs me that it’s been swapped with a motor from either a CX7 or a gen 1 motor. Now I wasn’t informed of this when I bought the car, so I was wondering if there as any sure way to prove that it’s a gen 1, as that’s the only way the dealership, will take it back. I know the valve covers are different but do they have a serial number on them anywhere or any way to prove that it’s a different motor to them? Any help would be greatly appreciated

 

Internals are the same. CX-7 turbo is smaller and valve cover has different baffle. If you bought those yellow coil packs on Amazon, send em back. Been well known to suck for nearly a decade. Ngk Plugs from Amazon are common to be fakes and break apart. Get the new oem plugs from a reputable vendor and set gap 0.026 to 0.028. Many approved vendors here sell the legit ngk plugs.

Still a code after oem part swap, then look into fuel injector seals leaking (get corksport). Then also look to getting injectors cleaned. Your mechanic who has familiarity with the speeds should know this all.

Oddly enough, I have heard of this story about a CX-7/ 1st Gen before. Recently.

 

They're the same, and that would be a bullshit reason to not help you out.

 

The gen pu has a different design on the piston face. You would need a scope to confirm but put has a smiley face while the rest have a pretty standard dish with small reliefs for the valves