Cylinder #2 Misfire- Engine Code P0302. We replaced out #2 coil pack, replaced out all the spark plugs, replaced the cam sensor. Start rough on and off, sporadically. Always runs fine though after I w

You might want to try and take the number 2 cylinder spark plug out and look at it it should be a Gray or very light Brown color.
It's also possible that there's number 2 spark plug had water splashed on it and it was very hot and could have cracked the porcelain on the spark plug. Does your Buick have over a 100000 miles on it or near a 100000 miles if so they may be original spark plugs and need to be changed you can try one Thing, try changing number 2 spark plug with number one or number 3 and see if the problem moves with the spark plug, if it does the spark plug is definitely bad if it doesn't you may have to start looking at the spark plug Wires or maybe even the fuel injector but, you can do the same thing with the fuel injector change it with number 1 and see if the problem moves. Shield injectors usually just pull out of the fuel rail but be careful there's an O ring on them don't lose it it should stay on but you never know.
Anyway good luck to you

1-5-3-6-2-4 https://www.youtube.com/watch?v=ZXXS3vdbZ5U

P0300 multiple misfire
P0302 misfire cylinder 2
P0306 misfire cylinder 6

P0300 - Random/Multiple Cylinder Misfire Detected
Basically this means that the the car's computer has detected that not all of the engine's cylinders are firing properly.

A P0300 diagnostic code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.

Symptoms may include:
* the engine may be harder to start
* the engine may stumble / stumble, and/or hesitate
* other symptoms may also be present

Causes: 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

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.

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.


P0301 Code - Cylinder #1 Misfire
P0302 Code - Cylinder #2 Misfire

A P0301 or P0302 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #1 or #2

Symptoms may include:
* the engine may be harder to start
* the engine may stumble / stumble, and/or hesitate
* other symptoms may also be present

Causes: A code P0301 or 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

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.


Hope ths helps. Keep us updated and remember to rate this answer.

Misfire 2 Cyl generated DTC P0302 Code - Cylinder #2 Misfire

A P0302 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #2.

Symptoms may include:
* the engine may be harder to start
* the engine may stumble / stumble, and/or hesitate
* other symptoms may also be present

Causes: 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

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.

Hope helps (remember rated this).

P0302= # 2 cylinder misfire,
check plug,plug wire,injector or coil

Cylinder #2 Misfire Detected
What does that mean? A P0302 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #2.
Symptoms Symptoms may include:

• the engine may be harder to start
• the engine may stumble / stumble, and/or hesitate
• other symptoms may also be present

Causes 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

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.

cylinder number 2 has a misfire

The concern is likely caused by the coil which sits on top of the spark plug. Your P0301 indicated misfire on cylinder 1. Your P0316 indicated it occurs on the first 1000 revolutions. Your P0171 indicated lean on bank one. Bank one includes cylinders 1,2,3 and 4. Your lean code is strange but could be related to misfire. I would recommend swap the coil on number one with number two. Clear the code and drive it. I would expect to see a P0302 which indicates the misfire traveled with bad coil. good luck.

The P0302 Code points to a misfire detected on the # 2 cylinder. If its stumbling, I would first suspect the plug or wire is bad. I believe the ignition coil on that vehicle is a single coil pack with four terminals, so if only the P0302 code is coming up I would start with the plug and wire. May be time to do a tune up and just replace all the splugs and spark plug wires.