Toyota Repair: 1999 4 cyl Toyota Camry, toyota camry, dear sir

Question
Dear Sir:

 Pusuant to our correspondence yesterday,I will reiterate the car problem.The above vehicle has 86K miles.It has a slightly rough drive idle speed.Additionally,a slight roughness in acceleration is present between 1750-2000 RPM.The check engine light appeared.The p 301 fault code indicated a missfire in cyl no 1.I replaced the no.1 plug and all ignition wires.Subsequently,the check engine reappeared.I do not desire to change parts randomly.Please indicate in detail the basic troubleshooting sequence.Thanks

Answer
There is no doubt that there is a misfire in the number one cylinder, since you have already changed the parts you have mentioned with no improvement you may need to have the engine compression tested to make sure there is not a compression loss in the number one cylinder, this is the first step before proceeding with any other parts replacement.