abecedarian

pinging maybe? like a bunch of bb's in a tin can?

weak coil or ignitor module?

yota4life6

abecedarian-
thanks for the reply
Its more of a rattling noise than pinging..but the bb's in a can comparison is pretty close for sure. Can you elaborate on the inspection and repair process for the weak coil and ignitor module... WOuld these items be causing any of my problems above?
side note.....grew up in Atlanta and currently (temp relocate) in California....
THANKS AGAIN..

SLOWBOOST

if you are not moving and the vibration is present, there is no need to check driveline.

is the rattling audible from any other point around the engine or just thru the intake? is the truck missing for sure causing the vibration, or just vibration? you can check the motor mounts by having someone watch the engine, put the truck in gear with brake applied and press the gas pedal slighty. Youll be able to see any abnormal shifting if the mounts are bad. You can start unplugging things to see if the condition stays the same or worsens to narrow down your troubleshooting.

how is the condition of the crank pullies on the front? the rubber deteriorates over time. has the transmission been changed recently or pulled out for any reason?

abecedarian

the coil is kind of hard to describe, but if you understand electrical transfomers, it becomes a bit easier.
the coil is basically a step-up transformer where one set of wires is wrapped into a coil surrounding another wire wound into a coil. when one wire gets charged with voltage and then the circuit is broken it causes voltage to be induced into the other wire but at a higher voltage due to the ratio of coils from one wire to the other.
the secondary voltage discharges through the sparkplug wires and causes a plug to spark and ignite the air-fuel mixture for a particular cylinder.
so a weak coil means that the resistance within the coils of wire is either too high or too low and that causes the sparkplugs to not fire properly.
now, sparkplugs not firing properly can cause either the spark to occur too soon or too late and that affects how much of the gasoline gets burned.

and off to the ignitor.
on older engines, there were 'points' that controlled the current going to the coil- they were mechanically opened contacts. when they opened it caused the coil primary to 'break down' and that caused the secondary voltage to occur and propagate through the center wire, to the distributor, then jump across the rotor to the terminal that lead to the sparkplug and then 'bam' a spark that lit the fire in the cylinder.
so in essence, the ignitor takes the place of the points of an old engine. It's not that simple, but kinda-sorta works.
if the ignitor isn't operating properly, it could cause the signal to the coil that fires a sparkplug to not occur at the right time.
there are feedback mechanisms built into the ignitor that can tell the computer that a spark occured and can also tell the computer that fuel was burned.

as far as test procedures... the easiest is swapping parts out.

I should add that there are a set of hall-effect coils within the distributor itself that generates signals for the ignitor and ECU to use to determine when to fire a sparkplug as well.

yota4life6

thanks for the replies guys...
The pinging/rattling is only present through the intake, but I can hear it load and clear, even with the hood closed and Im inside the truck. Pretty loud.

The miss causes the vibrations even sitting still at 1500 and 2500 rpm's.....so, while cruising down the interstate at high speeds (usually around 2500 rpm, the truck shakes like crazy. SO I am assuming they are related. TO be honest, I have listened and felt for vibrations so much since I got the truck trying to figure things out, I may be going crazy...lol..

is it worth changing the slighty expensive 02 sensor? Can that cause such vibrations?

thanks again, all input is appreciated..
neal

Noltz

You can unplug the 02, and the system will revert to safe maps. But I don't believe that would cause your problem.

Please check your MAP sensor vacuum line, and unplug your knock sensor. I've had similar problems in Corolla's with bad MAP's or the vacuum line to them (common for a backfire to knock them off). And it would explain your black plugs. The knock sensor being unplugged may throw a code but it should still run.

Good luck.

sh0kk86

my truck does this sporadically, and im thinking it might be my motor mounts, gotta check in the morning.

notjustatoy

Check the u-joints. I had the same prob but it was at all speeds. If the shaking is as bad as what you say, i'd def. check those joints. Most the time the problem is on the rear driveshaft. Just my $.02

Might not be the fix but still worth a try

NicCantDecide

If the problem happens in every gear AND in neutral at the SAME RPMs (which is what he stated)...its not the driveline.

If it were the driveline it would only happen at certain speeds regardless of RPMs and only when the truck was in motion.

mumme

fairly common problem. its one of your fuel injectors going bad.