how is the oil pressure? and how many miles are on the motor?

also try and crank it up at night or in a dark area and see if you can see a spark off one of the spark wires, could be a bad one. i know i have had that problem and may have it again right now. just a manufacturing defect probably.

 

The truck only has about 65000 miles on it. Oil pressure looks good. I will check for the spark tonight. Thanks!!

 

I checked for the spark and it all looked okay. Back to the drawing board!! I may try adding some octane booster to it and see if it goes away. If it does at least I will know where the rattle or tapping is coming from.

 

I just added some octane booster to it. I guess it will take a little driving around to get it mixed in with the gas. I used the Champion brand octane booster. I have already driven about 4 miles or so and it has made no change. The next step will be to check all my pullies and tensioners.

 

When you "checked for spark" did you rev the engine and have someone look for a flash under the hood?

Sorry, but octane booster won't make this go away. It's either a lifter, injector, or could be a bad plug wire.

 

I didn't have anyone rev the engine, but I will tonight. Like I said before, I have added MMO to the oil (16oz) and so far has made no change. Also, I can't hear any ticking at idle. What can I look for in an injector? If one is bad, would it be louder than the others?

It sounds just like a valve rattle at times, but with all the octane going thru the truck I don't see how that could be it either. It's not a very loud sound, but loud enough to hear it while driving. I figured the octane booster would be a shot in the dark, but at least it may eilminate it being spark knock.

Thanks!!

 

put a auto stethoscope on each injector you'll notice a difference in a bad one. Also, you can try to position the stethoscope over the valve covers and see if you notice a different sounding lifter.

 

Thanks for the info, I will try that this evening

 

I checked the lifters and they all sounded the same with no loud tapping. I also checked all the fuel injectors and they all sounded the same also. (I am checking these with a mechanics stethoscope). I did notice one thing coming home, it does not make the noise while the engine is cold. It is only after the engine completely warms up. While checking the lifters and the injectors I had my daughter rev the engine while I used the stethoscope. (Maybe I need to rev the engine and let her check for the tapping/rattle!!)

 

I also checked the spark plug wires and there is no arching. I did hear the noise while I was under the hood but it is hard to pin point the sound. It sounds like it is coming from the front area of the engine. I could only hear it when my eight year old was reving the engine. This Saturday I will try it again, the truck is so loud I am probably driving the neighbors nuts!! I will get the wife to hold the rpms to the point where the sound starts.