Why is no.1 plug sooting up?

P1401 Differential Press Feedback EGR Circuit High Input
Your EGR port is plugged. Replace your EGR valve, and clean the ports
A code P0302 may mean that one or more of the following has happened:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer
• A code P0305 may mean that one or more of the following has happened:
  
  • Faulty spark plug or wire
  • Faulty coil (pack)
  • Faulty oxygen sensor(s)
  • Faulty fuel injector
  • Burned exhaust valve
  • Faulty catalytic converter(s)
  • Running out of fuel
  • Poor compression
  • Defective computer
  • A code P0301 may mean that one or more of the following has happened:
    
    • Faulty spark plug or wire
    • Faulty coil (pack)
    • Faulty oxygen sensor(s)
    • Faulty fuel injector
    • Burned exhaust valve
    • Faulty catalytic converter(s)
    • Running out of fuel
    • Poor compression
    • Defective computer
    • A code P0302 may mean that one or more of the following has happened:
      
      • Faulty spark plug or wire
      • Faulty coil (pack)
      • Faulty oxygen sensor(s)
      • Faulty fuel injector
      • Burned exhaust valve
      • Faulty catalytic converter(s)
      • Running out of fuel
      • Poor compression
      • Defective computer
      • p1409
      • EGR Vacuum System Leak - Read Our Article on EGR Valve Codes For Help With This Oldsmobile Check Engine Light Code

Three things you should check using a good code checker which can read sensor outputs - the throttle position sensor (TPS), the mass air flow sensor (MAF) and the EGR valve. While you are at it, replace the PCV valve.

Clean MAF , and replace throttle position sensor .

Hi my vectra did this and didn't show a fault code it's the crank shaft position sensor located behind the starter motor on the front of the engine the sensor is about 30 pound mines never cut out sins i change my spark plugs and coil pack to trying to figures out who knew it was a little sensor it through a your crank shaft outta wack and it throws through a lot of petrol otta timing cheers scott

usually this code is followed by another number 1-4 or 1-6 or 1-8 depending on how many cylinders your vehicle has ,, what the code you got is a basic P0300 Random/Multiple Cylinder Misfire Detected A code P0300 may mean that one or more of the following has happened:

• Faulty spark plugs or wires
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector(s)
• Burned exhaust valve
• Faulty catalytic converter(s)
• Stuck/blocked EGR valve / passages
• Faulty camshaft position sensor
• Defective computer
• I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
  Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck ope
  

well it is a missfire the timing may be the issue here

A code P0303 may mean that one or more of the following has happened:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer

Possible Solutions If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

A. P0401 "Exhaust Gas Recirculation Flow Insufficient Detected" that there is not enough exhaust gas being admitted to the engine.
There are a number of things you can check, and others you need a scan tool to check.
What you can do is check for vacuum to the EGR valve. You can remove the EGR valve and see if it is stuck closed. Test it with a hand vacuum pump and see if it opens smoothly. Check the EGR valve orifice and make sure it is free and clear. Check and clean the EGR passages in the going to and from the EGR valve.
If this checks out, then the Differential Pressure Feedback EGR system will need to be scanned to check the EGR sensors and switches

A code P0301 may mean that one or more of the following has happened:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer

have you replaced coil pack? Check EGR passage through upper mainfold and make sure clean. also make sure EGR valve not stuck part way open. Also check crank and cam sensors along with MAF.

A multi misfire may mean that one or more of the following has happened:
Faulty spark plug or wires, Faulty coil (pack), Faulty oxygen sensor(s), Faulty fuel injector(s), Stuck/blocked EGR valve / passages, Faulty camshaft position sensor, Defective computer.

The engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wire, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the the problems were faulty fuel injectors. 

Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.

Good luck and hope this information helps, keep me posted, be glad to help you get the truck running 100% again. Not sure if your running a K&N air filter, and if you are there may be a flim of oil on the MAF sensor that is making you run lean. You may want to spray down the MAF sensor with a can of MAF cleaner. 

check spark plug wire they may been put back
in the wrong firing order