Audi a6 misfire p0300 p1296
 

About a month ago I got a misfire in cylinder 5 in my 2000 audi a6 2.7 tip. It was misfiring at partial to full throttle.
I replaced the coil and it fixed the misfire. About a week later I got another misfire but it's only at 13-15psi no matter what RPM.
I read the code and it was on cylinder 6 and a 1296 code (air/fuel metering)
I swapped the ICMs on the air box and there was no change. Still misfiring on cylinder 6.
I swapped the coils from cylinders 2 and 6, then cleared the codes. If the coil is bad, the misfire would go to cylinder 2. Then it gave me a p0300 code-Random misfires, and the 1296.
I changed the fuel filter, thinking it may not be getting enough fuel, but that did not help either.
I also tried cleaning/unplugging the MAFS and Coolant temp sensor (which is new) but no luck.
It still only misfires once the turbos are spooled.

I've looked around many threads but could not find a solution. Any help is much appreciated, thank you!

What color is your new Coolant Temperature Sensor? There was an updated "green" sensor that came out around 2002 year to replace the older black one.

Another question, when was the last time your thermostat was replaced? Possible it may be stuck open? If your coolant is not reaching normal operating temperature, this could cause issues with the air/fuel metering and is probably related to your misfire. I mention this becuase you said that you have already replaced the CTS and don't feel that its your issue. You also made no mention of the mileage on your car, which most of the time can be helpful with diagnosing mechanical issues.

I apologize. It has 152,000 miles and the thermostat was replaced about 50k ago. The CTS is green. I bought an OEM one. I hooked my car up to a scanner and my coolant got to a temp of 183 after idling for 15 minutes. I am thinking the cats may be clogged though. It has been getting worse day after day. I might try gutting them and putting in spark plug defoulers on the o2 sensors to keep the ECU happy.

Today I decided to check all the plugs again, cylinder 2 plug was covered in oil. From what I read, oil leaking from the valve cover gasket, fouls out the plug. I guess it's time for new gaskets.

I put new valve cover gaskets on. Cleaned the oil from the spark plug valley, and put new plugs in. Still the same issue. I will most likely bring it to a Euro shop down the street and see what they can do, even though I never let anyone else touch my vehicles.