Help! 97 Blazer misfires, rough running, arcing

Update...problem solved!!

New to the forums, been doing ALOT of reading here on problems, searched for similar issues and tried methods explained.
Have attempted to rectify, but no luck so far....
97 Blazer 4.3 Vortec w/ 103K on it.
Problems started after replacing plugs and wires. the followling day, it just started running really rough.
I had a misfiring #4, wasn't getting fuel so replaced the injector.
(Replaced 2 & 4 actually)
Since then, I have:

Rplaced plugs (Autolite Platinum)
Replaced wires
Replaced fuel filter
Replaced Distributor cap (one w/brass contacts)
Replaced rotor
Replaced Coil (had blue constant arcs on each side)
C/S EGR valve (twice)
C/S Throttle body (very dirty)
Cleaned little wires in MAF
Cleaned MAP sensor
Swapped plugs/wires trying to stop arcing.

Could it be the plugs? or ignition control module?
Now its even worse. When I try to drive, it sounds like a freakin helicopter. Idle is rough and seems like its gasping at times.
I can hear arcing intermittently in different areas of engine.
I am at a loss here. I have worked on this for the entire weekend, and I'm out of ideas. There are currently no codes. Previously, it was this or that cylinder misfire codes.

Did you ever get the computer scanned for codes?

How is the fuel pressure?

What did you gap the plugs too?

I bought a code reader rather than drive to Autozone every hour to check codes with a truck that was half running and shaking at stop lights -

Misfiring codes among mostly cylinders 2 & 4, and occasionaly cylinder 3 depending on how much I tweak the wires to keep them away from metal and other stuff.
I erased the codes, ran the engine, and rechecked the codes, then
swapped plugs/wires across sides to see if it helps. Seems some plugs arced less when set at .55 vs .60, but it could just be me.

Completely frustrated and cannot figure this out - Searched this forum for hours and went over the repair manual several times.
Many references for fuel pressure testing - will try that next if I don't don't lose my sanity.

banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead:

If you have to worry about the new wires touching metal, either you have high resistance at the plugs or a bad set of wires. Personally, I stick with AC plugs and wires.

I bought a code reader rather than drive to Autozone every hour to check codes with a truck that was half running and shaking at stop lights -

Misfiring codes among mostly cylinders 2 & 4, and occasionaly cylinder 3 depending on how much I tweak the wires to keep them away from metal and other stuff.
I erased the codes, ran the engine, and rechecked the codes, then
swapped plugs/wires across sides to see if it helps. Seems some plugs arced less when set at .55 vs .60, but it could just be me.

Completely frustrated and cannot figure this out - Searched this forum for hours and went over the repair manual several times.
Many references for fuel pressure testing - will try that next if I don't don't lose my sanity.

banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead:

How old are the cap & rotor?

Its Fixed!!

After reading over the forum, I decided to put in the AC Delco Platinium plugs. Absolutely amazing change. Runs like new. I cannot believe the plugs make such a difference - No arcing, no misfires, no codes, no rough idling. What a kick in the shorts.

Yea, AC Delco Platinums are the best for our trucks.

Good to see you found the problem.

I will keep this in mind when someone else has a problem like this.