1. Are the new plugs DENSO K16TR11 or NGK BKR5EKB-11? Gap correct? (0.039-0.043")
2. Check vacuum hoses for bad fit or cracks.
3. Check injectors of 2 and 5 for correct voltage to open (9-14 V) and function.
4. Check resistance of injectors of 2 and 5 and opens and shorts in wiring harness for injectors.
5. Check fuel pressure and volume
6. Check MAF meter and ECT sensor
7. Check compression, valve clearance, and valve timing (timing belt).