Why is there a cylinder 2 misfire?

PULL THE WHITE OR CLEAR CONNECTOR AT THE PCM,,,CHECK THE WIRE AT PIN 18 (BLACK WIRE / WHITE STRIPE FOR GROUND.
The following is a summary of the instructions included with the service kit:
1. Remove the negative terminal from the battery.
2. Move the wire located at connector J3 (WHITE/GREY/CLEAR), pin 18 to connector J1 (BLUE), pin 23.
3. Install the jumper wire between connector J2 (RED), pin 26 and connector J3 (WHITE/GREY/CLEAR), pin 18.
4. Install the tag included in the kit around the VCM wiring harness. This tag notes that the wiring harness has been modified.
5. Reconnect the negative battery terminal.

Road test to verify that the condition has been corrected. If any of the following conditions are noted, the transmission should be repaired or replaced using the most cost effective method. Canadian dealers should repair the transmission.
1. Transmission fluid oxidation or excessive sediment.
2. Transmission slip or flare after this service fix is performed.
3. DTC P1870 is stored on a 4L60-E (M30).

The following tools are available from Kent-Moore (1-800-345-2233) for use in removing and relocating the VCM wires:
1. J 41758 Terminal Tool; used to remove the wire from the VCM connector.
2. J 41759 Punch; used to punch a new hole through the connector seal

Is the check engine light lit ? Any DTC'S - diagnostic trouble codes ? What engine ? 4.3 L vortex . Leaking fuel pressure regulator under the upper intake manifold . Leaking fuel injectors ! Ignition timing problem . How does the engine run ? Who installed the plugs an wires ? are they right ? Fuel pressure leak down test, fuel injector balance testing . Check distributor drive gear an slop in the shaft . Did you have distributor out ? Is it in the proper position ? What cylinder is misfiring ? engine mechanical problem ! What do spark plugs look like ? fouled , soaked with fuel . Do a engine compression test .
The camshaft drives the distributor shaft which rotates providing a spark to the correct cylinder by way of the cap and rotor. The camshaft position sensor functions much like the crankshaft sensor previously described but provides only a 1x signal to the VCM. That is, for every 2 rotations of the crankshaft, there is 1 rotation of the camshaft. Note that the CMP sensor will not affect driveability. The sole purpose of the CMP sensor is to provide the VCM with the necessary information for the misfire DTCs.

PO300 and P1399 are random cylinder misfire detected.
PO301 cylinder 1 misfire
PO302 cylinder 2 misfire
PO304 cylinder 4 misfire
PO306 cylinder 6 misfire
I would say that you have damage to the ignition wiring harness or you ECM is failing.

run a compression test on all cylinders to rule out head gasket or burned valve.

The injector is bad , internal coil when heated shorts out . Feel lucky it's only one injector . It could be like this corvette all injectors Quit when hot ! Test the injector with ohm meter . Chevy Corvette No Start When Hot The Diagnosis

have you performed a compression test?a cylinder with low or no compression will cause a misfire

Yes it could but you should have fault codes stored for this, has it been scanned for fault codes? Autozone does this test for free as well as other parts stored.

Replace the coil for number 3 cylinder.

first cylinder 4 is the last on the passenger side . first pull the coil out and check if there is water where the plug is. if there is take the water out and dry up the coil. if you find water you got a crack manifold or a bad intake manifold gasket. if there is no water replace the coil. good luck

check your wire harness on the top of the engine. Volvo must have bought harnesses from Mercedes. The insulation just cracks and disintegrates, then the wires short. Not good for an ignition system.Once they short It can fry the circuit for that cylinder in the computer. Does not set a code other than Misfire.