P1399 on cylinders 2-6: 02 EX V6

EF-Jordan · Oct 1, 2015

It runs rough the whole time the car is running hot or cold and thru all rpm's. Cylinder misfire codes for cylinders 2-6 and p1399 for multiple cylinder misfire. So far I changed the spark plugs and the ecu so far with no change in how it's running. Also swapped the coil pack from cylinder 1 with cylinder 4 and cylinder 1 still no misfire. Confused on where to go from here since cylinder one is acting fine. No other codes besides misfire codes and haven't checked anything else. Help! I was going to check the EGR valve and make sure the ports werent gummed up.

xci.ed6 · Oct 2, 2015

Does it ever act funny at specific times?

Like hot restart, while cold, anything.

EF-Jordan · Oct 2, 2015

xci.ed6 said:
Does it ever act funny at specific times?

Like hot restart, while cold, anything.

From the time I start my car and thru all rpm's its misfiring.

spacemonkee23 · Oct 2, 2015

clean your EGR, if it continues do a Valve adjustment.

You could do a seafoam treatment to help clean the valves and see if that helps first. 1/3 bottle in gas, oil & through the intake manifold.