#1 Cylinder misfires. electrical problem

Question edited for clarity. Full year make model in title and mis-spelling of 'misfire'.
Question moved to sub category.

The misfire code only tell you that, unfortunately it doesn't tell you why. When swapping parts to test theories, only swap one thing, one cylinder to one cylinder and only one item, the coil, the plug or the wires, not all three. What was the make of the Crankshaft Sensor? Only buy quality OEM replacements as there is a history of bad ones from Mexico and China.

Wouldn't hurt to check the wires again. This has a neat diagram.

https://www.silveradosierra.com/threads/5-3-firing-order-cylinder-diagram.734633/

..

have a compression test done and look for a moving valve seat insert
it gives the knock, misfire
as it is no 2 cylinder it is mechanical because you have moved the injectors and coils , plugs and leads and it stays at no 2 cylinder
If you want clean engine oil then change the synthetic oil out and put in diesel oil 20w40
It will not harm the engine as it is the same as petrol oil but with more additives than petrol oil
it is cheaper and has heavy detergent properties that keeps the engine internals clean
from the gunk in the sump ,it is clear that changing engine oil on a regular basis is something you don't do but if you want a reliable long lasting engine , it is must do number 1

What DTC code(s) are you getting?
You performed a compression test on cylinder #1; did you test cylinder #2?
Compare the readings, if there is a significant difference in compression readings between the two, you may have a bad head gasket, a bad valve, etc.
The bottom line, the problem is internal to the engine.

misfire,
only on cylinder #1
bad spark plug or wires to it or COP coil to it.
bad injector
bad injection signals
low compression on #1

there are simple tests for each, i will not ever guess on misfire.

misfire means, in English (not slang)
THIS Cylinder #1 had weak power during the POWER stock.
The ECU computes Velocity of each power stroke and Reports the weak.
even an air leak to #1 intake runner can cause this
or the injector #1 base gasket leaking. Air.

but it is not fibbing it is weak. #1

You forst need to see if that cylinder is getting fuel, this requires an injector flow test be run by a dealer or a well equipped shop, also you at home can check for intake manifold vauum leaks with a can of carburetor spray. You should also run a compression test on all cylinders and see if that one cylinder is lower than 5% from the hightest reading.

Time to do a compression and cylinder leakdown test

check the injectors with a noid light you may find a bad one. if not check the compression.

One thing you didn't say you replaced was the plug wire. That could also be the problem.

YEP BAD COIL CLOGGED FUEL INJECTOR AND INTAKE LEAK TO CYLINDER 1.TRY CLEANING FUEL INJECTORS.IF STILL MISFIRE DO A COMPRESSION TEST TO THAT CYLINDER YOU COULD HAVE A MECHANICAL ISSUE.

1. Bad or fouled Spark Plug at #1 Cylinder.
2. Bad or misfiring Wire going from the #1 on the Distributor/Electronic Ignition Coil to the #1 Cylinder.
3. Misfiring at the #1 on the Distributor/Electronic Iginition Coil.

a. Unplug the #1 Wire at the #1 on the Distributor/Electronic Ignition Coil.
b. Using an Auto electrical testing: Probe, wire and ground clip electrical, stick the Probe into the opening at the #1 Distributor/Electronic Ignition Coil. Use the grounding clip - clipped to a portion on the engine.
c. Start the Vehicle and check for rhythmic spark.
d. If there is NOT rhythmic spark, the Distributor/Electronic Ignition Coil needs to be replaced.
e. Turn off the engine.
f. If there is rhythmic spark: Reconnect the #1 Wire at #1 on the Distrubutor/Electronic Igntion Coil.
g. Disconnect the #1 Wire from the #1 Spark Plug.
h. Again using an Auto electrical testing: Probe, wire and ground clip. Insert the Probe into the end of the #1 Wire and clip the ground clip onto the engine.
i. Start the engine again.
j. Again Check for rhythmic spark.
k. If there is NOT rhythmic spark the #1 Wire needs to be replaced. (Replace all Wires as a Set).
l. If there is rhythmic spark then the #1 Wire is fine.
m. Turn off the engine,
n. Remove and Inspect the #1 Spark Plug. Clean if necessary and Regap.
o. Reinstall the Spark Plug and reconnect the #1 Wire.
p. Restart the engine.
q, If the code reappears:
r. Replace all the Spark Plugs.
Let me know if this helped or if you have additional information or questions. Feel free to contact me at FixYa.Com.