Running on five cylinders - Need expertise

General Description of Problem

Vehicle runs on five cylinders when at engine is fully warmed up (when restarted while warm but not after first start while warmed up)

Symptoms

- Steady check engine light (after around 10 minutes of running on five cylinders)

- Code 306 on ODB II code reader

- Intermittent flashing check engine light (no more than five seconds at a time; at least one minute between occurrences)

- After first start of the day, vehicle will run fine for at least four hours as long as the engine is kept running and not turned off

- If the engine is turned off after fully warming up:

-- Engine will run normally if restarted within 30 seconds

-- Engine will run on five cylinders if allowed to sit for 10 minutes or more (not running) and then restarted

- After running on five cylinders, the only way to get engine to run normally again is to allow engine to fully cool (not running for at least two hours)

- Attached timing light to # 2, 4 & 6 wires while engine was malfunctioning

-- Got strobe lights each time

-- Could not attach timing light to #1, 3 or 5 because of engine design

Actions Taken

- Replaced spark plug on #6 cylinder

- Replaced spark plug wire for #6 cylinder

- Swapped coil packs on top of #1 and #3 cylinders

Looking for any experience with or suggestions on how to fix. Thanks.

 

The year model 4Runner would help.....I'm guessing a 96 through 2002 V6?

How do the spark plugs look? usually the one that is not firing is fouled really bad.

 

Sorry. 2000 with 3.4L. I did replace the plug. The old one was clean and had been replaced sixth months ago.

 

I had a 2001 Tacoma with the 3.4L and I got a Misc. Misfire cylinder #1 ended up being a bad fuel injector.

 

You were correct to try replacing the plug, wire, and coils first. However, since none of that worked, replacing the fuel injector will most likely solve your problem.