Squirrel: After reading this thread beginning to end, I feel strongly about either a CPS or an exhaust leak. Check your manifolds well for any hairline cracks, as the engine heats up, the cracks could be expanding causing your ping.

 

Jr. Mechanic's suggestion of
checking the Crankshaft Position Sensor (CPS)
is a good one,
as it is down there where
water/dirt/stones can suddenly hurt it,
and if the CPS is somehow going slowly bad
and misses one or more of the notches it needs to sense
that would cause an intermittent misfire
that would show up
suddenly

 

Dude hank, I got a question: Do you talk like that in real life? I'm just wondering, haha.

 

writing that way
on purpose
with short lines and word groups
is called 'chunking'
and is designed
so that
you can read it faster
and perhaps
understand it better

it is based on the idea
that we don't read letters
or even whole words
but the human mind grabs
'chunks' of what are really thoughts
as it sees sentences

this is also one of the ideas
of speed reading

you might count the words in one of my posts like that and see if you think you can understand the complex ideas better than someone who writes one long paragraph with many ideas or instructions with no breaks and decide for yourself if you were in highly stressful situation where people were shooting at you and some of your friends were hurt and wounded and it was highly critical that you exactly read and understand a set of commands that it might be life and death for you to carry out as quickly as possible without delay or where you have to read something more than once

Chunking is a
German Army invention
also used by
the Israeli services

Chunking was taught by
one particularly good instructor
years ago at the
Mine Safety & Health Administration (MSHA)
academy in West Virginia
for use in stressful mine rescue situations

 

Wow, you're right... Thats kinda weird how much of a difference that makes...

 

I have haerd taht eevn if you wrtie wodrs with the frist and last letetrs in the corerct places, you can still raed it claerly no matter how pourly its spelled.

 

Well, back to the problem with an update:

The engine is cold so I'll check the headers for cracks. Mani's were replaced a month and a half before this happened so it's possible there's a leak where the header meets the Y pipe. I've checked the torque on the bolts every week since I've installed them to make sure the bolts are tight and they didn't ever move after the first week.

It isn't the O2's, I replaced those. It was due so, I figure preventative maintenance. Also, I had the cat cut off and inspected. It's fine.

Got a new magnaflow 5" X 8" X 24" muffler put on, and the drone is finally gone and cab ride is enjoyable. I can hear the exhaust but i can also tune it out if I desire. The old muffler was 5 X 8 x 18. What a difference 6 little inches of muffler makes.

If it were the crank sensor, wouldn't it happen cold or hot? Certainly base timing could be advanced, and the higher octane would compensate for the advancement of the timing on the lower tune, but I would think that that type of defect would be system wide regardless of engine temp.

 

if the crankshaft position sensor
was only partially bad
it would not be surprising to me
if hot or cold did make a difference
because metal expands and contracts
with temperature change
and the gap from sensor to notch
probably changes one way or the other

note to self:
build next pickup completely from INVAR
using my share of bailout funds

http://en.wikipedia.org/wiki/Invar

 

You know, I accidentally forgot to pay a bill to Citibank last month and got charged a $41.00 late fee penalty.

Do you think I have a valid argument for not paying the $41.00 penalty since they were just given $325 billion from the federal government for not being fiscally responsible?

Technically, I and every other American (including the ones too young or too illegal to pay federal income tax) just gave Citicorp $928.57, if we assume 350 million people.

 

I think I have figured out what the problem is.

I believe the intake manifold is literally falling apart on me. There is pooling oil in the plenum pan again after having just fixed it last Saturday. There are 2 large cracks running up both sides of the intake right where the throttle body sits, as well as the separation near the fuel injectors running along the runners as you see in the previous pictures. Basically, the manifold won't seal and it might as well be a plenum leak.

I will hunt the scrap yard for a replacement intake. Or look into purchasing an M1.