P1174 code after R&R of air filter and plugs

Question

I replaced spark plugs, air filter, oil filter and engine oil about 400 miles before the check engine light came on. Pulled a P1174 code. What are the simple possibilities?

Answer 1

P1174 Fuel trim cylinder balance

Sparkplugs properly torque down? Do MAF sensor cleaning, All air filter manufacturer has to apply a fire retardant to the air filter, this in return tends to contaminate the MAF sensor, just perform a MAF cleaning clear CK ENG LT , and retest.