2005 Audi A4 1.8T QT, cylinder 4 misfire p0304

P0150 = O2 Sensor Circuit Bank 2 Sensor 1.
P0300 = Random/multiple cylinder(s) - misfire detected.
P0304 = Cylinder 4 - misfire detected. You will need to get the car locked at in more detail to find out what it actually is.
You will need to recheck the P1931 code as I cannot find it listed.

P0346: Camshaft Position Sensor Intake Circuit Range/Performance Bank 2 http://www.autocodes.com/p0346_audi.html

P0391:Camshaft Position Sensor 'B' Circuit Range/Performance Bank 2
http://www.autocodes.com/p0391_audi.html

P0304: Cylinder 4 Misfire Detected http://www.autocodes.com/p0304_audi.html

P0306: Cylinder 6 Misfire Detected http://www.autocodes.com/p0306_audi.html

P0305: Cylinder 5 Misfire Detected http://www.autocodes.com/p0305_audi.html

P0300: Random Cylinder Misfire Detected http://www.autocodes.com/p0300_audi.html

P0300: Random Cylinder Misfire Condition
http://www.autocodes.com/p0300_toyota.html

P0301: Cylinder 1 Misfire Detected
http://www.autocodes.com/p0301_toyota.html

P0304: Cylinder 4 Misfire Detected
http://www.autocodes.com/p0304_volkswagen.html

miss fire check coils or plugs

If the check engine light is on? Take it to your local parts store for a free diagnosis. Usually it needs a tune up,spark plugs, cap and rotor if applicable. I don't do audi very offend but this is a start. good luck!

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/jeff_24365d731679262d

P0304 Code - Cylinder #4 Misfire Detected
A P0304 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 #4.

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 P0304 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.

A P0304 OBD2 code is "cylinder #4 misfire detected". The first place to start is your spark plugs. 1. Check condition and for wear. 2. check the spark plug wires or coil packs(depending on which you have).

Those are cylinder misfire codes. PO300 is random misfires (meaning 1+ cylinders misfired) and the other 2 codes are for cylinder #1 and 2. Did you change the ignition coils yet on 1 and 2?

Do you let the tank go to empty before refueling a lot?

replace the speed idle sensor

P1127 Long Term Fuel Trim mult.,Bank1 System too Rich

P1129 Long Term Fuel Trim mult.,Bank2 System too Rich

P1250 Fuel Level Too Low

P1300 Misfire detected Reason: Fuel level too low

P0154 02 Sensor Circuit No Activity Detected (Bank 2 Sensor 1)

P0300 Random/Multiple Cylinder Misfire Detected

P0303 Cylinder 3 Misfire Detected

P0304 Cylinder 4 Misfire Detected

It sounds like there is a lot going on.

Good Luck

Brian