Park your car in a dry area (garage?) and lay some carton or linnen under the engine. If you loose coolant fluid, then you'll see it on the linnen or carton.

If only 4 of your plugs show this problem, then i think its your ignition that isnt 100% set right. (too late or too early). If it would be the sea foam , then all your plugs would be suffering this problem.

Since this is an official chevrolet forum...

DO NOT BUY an OBD cable for only 15 dollars on ebay.
DO NOT download the FREE software available all over the web.
And DO NOT run a diagnostic all by yourself, even if it would mean saving more then 50 dollars. .

But of course...if you would...who could stop you?

 

I have done the bed sheet under the engine,no drips except from the AC condenser, its internal, I am sure, unless its so slow of a leak it dries up before it hits the ground, no traces though. My ignition is set by the Computer, so that would mean a sensor is bad if that was the case.

Anyways thanks for the brainstorm everyone, I will post back the problem in a few weeks after I take her the the Doc. (dealer)

 

Well all be dam, I repaired it. I had some time tonight to have both the truck and tahoe side by side and Here is what I found and repaired on my truck.

1. Super slow coolant leak- Used a mechanics mirror to look at the coolant hoses and found a wet spot on a hose under the water pump. It was external after all. I will repair that soon, I am going to replace all the hoses since they are pretty crunchy from living in AZ for 4 years in 120F at times, It could possibly be the water pump too, Ill look at that closer when I have time.

2. Loss of power & hesitations- Swapped the tahoes MAF with my trucks since it's the same part #( Delphi 25168491) then went for a test drive and $h** I almost ran into the guy in front of me at a light since I was so used to the lack of power. So I went out on an open road and floored it from a stop, Lit up the tires and took off like a bat out of hell! I dont like doing that cause it cost me maybe 5 bucks in tire wear. I drove it around a little and looked for any hesitation and none.

3. Oil on Spark plug threads- I pulled the one out on the # 1 piston that had the most oil on it, since I put the AC Delco Iridiums in it did not have any oil on the threads. So it must of been something between the sea foam,gas treatments & running poorly.

So I am in need of a new MAF and Id like to get the Delphi one at a good price, any suggestions?

Ill leave the bad one on the tahoe which didnt seem to be effected by it , werid, but I am going to replace it anyway.

So thats the end to my worries now, no I can be happy and work on cleaning it up and do a few exterrior mods.

Thanks to everyone here! This is a great forum, I have learned a great deal about my truck and general tech.

 

Well, I was going to recommend getting a MAF sensor from Standard, NAPA,Kem, or Filco, most decent aftermarket brands are twice as good at half the cost of O.E.M.

The other thing which might pertain here is the Vortec V8s(had this problem with my 04 Silverado 6.0 Vortec at 24K AND 48K miles) have really crappy waterpump gaskets. Fortunately it's an easy fix, as the pump is located higher on the engine than it used to be.
It's NOT buried under the PS, A/C, and A.I.R. pumps like the older V8s.

 

Thanks rivereye, I will do some searching right now. Yea , that water pump looks easy to get to if I end up finding a leak in it.