Some background. I have a 1998 Toyota 4Runner V6 2WD with about 150,000 miles. A few months ago the check engine light was flashing when I am travelling over 70mph. The dealership said nothing is wrong when I asked them to look into it. But I didn't get any codes from it. I read on-line that it could be a possible misfire so I changed the plugs and wires.
A few weeks ago, the check engine light came on and stayed on. I took it to a dealership to diagnosis the problem, they came up with Mass Air Flow sensor was shot. I replaced that, and reset the computer. It still comes on and flashes at highway speeds. I bought a low end computer to read the codes. I got P300 (Random/Multiple Misfire), P302 (Cylinder 2 Misfire) and P305 (Cylinder 5 Misfire). Cylinder 5 has the coil-pack and Cylinder 2 has the wire coming off the coil-pack for Cylinder 5. So I replaced the coil-pack. The light is still coming on and flashing. I was hoping someone could help me in figuring out how to stop the light from flashing. It comes on only when I am travelling past 70MPH. I have tried just rev'ing the engine up to the same RPM's as I am running when doing 70, but the light doesn't flash then.
Any help would be greatly appreciated.