I have a 104,000 miles on my 2000 4x4 with the 4.7L and on the way home the engine started to run ragged and misfiring and the check engine light started to flash. When I got home I noticed I had a small leak in my muffler that hadn't shown up until the engine misfire. Any ideas or help?

You'll have to pull the code, likely a coil went though for the miss-fire. I've replaced 2 already.

Here are the codes I pulled P0300-301-302-304-308-308P. Today I changed the plugs using OEM, new fuel and air filters, FI Cleaner, 15 gallons new gas. Ran for 20 minutes and no engine light but had a skip. I Shut down , waited 2 hours and when I started the engine again, the light flashes again and I get the same codes. What else can I do, loss of power, can barley take off but when I put in N and race engine it will go to 4500 OK but at low speeds it skips and putters. I really am appreciative for any help, I am 65 years old with stage 4 cancer and need my truck.

http://www.tundrasolutions.com/forums/1gen-sequoia/64227-p0300-p030x-engine-codes-misfire/

Did you pull some plugs off and mix them up?

I ran the truck for an hour, pulled the new NGK plugs and they have all soot on them. Could I have bad coils or wires?

Soot likely from the miss-fires. Check your plug gap, plug connections and firing order.

Thanks, I will to that tomorrow when the sun comes up. Do you think I have a coil issue, plus wire or C02 sensor issue also?

I re did the plugs, light went out for a while but engine skip was still there, after 5 minutes the light comes on and flashes fast. Would I have more then one bad coil to cause so many misfire codes?

Did you replace the coil? Every time this happens to me it is the coil. I have replaced 4 or so so far

you will have to unplug the coil at each cyl. one at a time while the engine is running, if the engine idles down plug it back in and move on to the next coil. if you pull the plug and you get no idle change thats the bad coil. if the check engine light is flashing that is telling you the truck is getting a code from a cyl. that is not firing. the cyl. that is not firing you can pull the coil and spark plug and ground the plug to see if the plug is firing and i'm sure it won't be. also if you have 4 coils that are not firing you have a bad bank and will have to replace the ECU. that is under the glove box and you have to remove the panel and it has 5 white plugs al going into a large bundle of wires (engine wires). some times a water leak from the winsheld will get the ECU wet and you will lose a bank (4 cyl.) of spark. if you just have 1 bad coil you will feel a lack of power but not that bad loose a full bank and the truck will run with no power. hope this helps...Art