Toyota Repair: 4Runner -, toyota 4runner, spark plug wire

Question
QUESTION: Hello, I have a 2000 Toyota 4Runner 2WD with a manual transmission. About 6 months ago we had to replace the engine. 3 months later, I noticed that it was starting to have some problems including: idle is rough; seems like it wants to die and occasionally does die out in 1st and 2nd gears; lack of power in all gears; check engine light is on and blinks when symptoms are occurring.

Initially this only occurred every once in a while, but now it is happening almost every time I drive. Sometimes when I'm driving and it is hesitating, the power will suddenly kick in and the problem seems to disappear for a little bit. I got the codes and was given this readout: PO300 ("random cylinder misfire condition") and PO301 ("cylinder 1 misfire detected"). Any suggestions on what could be causing this or where to start? Thanks for your input.

ANSWER: I only need to know if it's a V-6 or 4 cylinder engine.

---------- FOLLOW-UP ----------

QUESTION: It's a 4 cylinder engine.

Answer
The misfire is isolated to the #1 cylinder, there could be several causes for this: A malfunctioning ignition coil, a bad spark plug, a bad spark plug wire, a malfunctioning fuel injector, a tight valve or a loss of compression due to a leaking valve. I would start by removing the spark plugs and checking them as well as the ignition coil pack for any signs of electrical arcing to ground. These are the most common.