Ironically I am running the cheapest autolite for trucks available and they work great in my truck so far! Nothing wrong with Bosch at all, I agree with Merc its the irridium ones that cause the issues.

 

^^^ I have a spare box of the same Bosch plugs I am using and a box of +4's. I will send them out to you so you can try them.

Merry Christmas John

 

I have been trying to get some information off my scanner to see if if might compare as "normal". My O2 sensors read 1+ volts to start with and drop as the engine warms up. the system goes from being open to closed but some of the "warm" voltages are only a tenth to a few hundredths of a volt. My temp. sensor has been reading 180-184 which is not 195 (what the t-stat is)but I don't know where the PCM would consider the engine cold and what it would do to adjust for it. I have been pulling 9" to 21" vac.. Lastly, the timing advance will go into the low 40's when accelerating. Thanks to everyone for your help and interrest

 

O2 should bounce between 0 and 1 volt in closed loop. Voltages before that are not really relevant, as the PCM ignores it anyway.

Running a bit cooler will cause the PCM to richen? the fuel mixture to help the motor warm up some. (I could be wrong on that though, it might LEAN the mixture, as that tends to make it burn hotter.... which could possibly give you a lean-burn miss..... bears some looking in to.) As a test, unplug the O2 sensors, and drive it. It will set a code, but, see if the miss goes away.

Should have around 20" vacuum at idle, less as the throttle opens.

 

PS it's snowing today, I don't have a garage, so I'm going to see about the valve springs tomorrow

 

Well, I tried new plugs recently and unplugging the O2 sensors earlier. Then I thought about the vacuum. Mine is 10 or 11 at idle and goes up to 20 with more throttle. I pulled the TB off and looked at the intake there was a small amount of oil at the back. I guess that's why 6&8 are misfiring because the pick up for the runner is the farthest back. I'm so disappointed, from what I can see I laid a nice uniform bead of grey RTV above and below the gasket. I must have just missed a spot. Stay tuned for round 3.

 

Use the Fel-Pro gasket, and NO RTV. Much better success rate.

 

Third time is a charm! No RTV with Fel-Pro gaskets and I torqued the plenum to 85 in.lbs. not 84 just to make myself feel better about it. There looked to be a 1/8 gap in the RTV from the last time. It was hard to tell, I had to knock the plate off with a rubber mallet so it smeared the oil around making it harder to diagnose. The CEL has not come on, no codes. It still idles a little rough and stumbles some going into 4th but it definitely has more power. It is only pulling 10" vacuum cold but I'm not going to worry too much over that number. I did the whole thing in about 7hrs this time compared to over a week that first time! You know you've done it too many times when you know the size of the socket you need next!
Thanks for everyone's help.