‘01 4.4i misfiring when cold

[Jakal702]

Hello,
Recently my 2001 4.4i has been misfiring but only when cold. I keep reading codes and they all seem to be random misfires with fuel cutoff. I changed the spark plugs and installed new Bosch platinum plugs (figured it might be a good idea as the car has 122k miles) but this did not solve the issue. It misfires upon start up and when cold, but once the car is warmed up it runs fine. Can anyone help me pinpoint the problem?
Thanks

[CapeX5]

Any "lean" mixture codes? Thinking a leak in any of the intake hoses or vacuum lines. You might want to do a fuel pressure test. Odd that it only does it when cold. And, at this point, the injectors come into question as well.

[Jakal702]

Originally Posted by CapeX5

Any "lean" mixture codes? Thinking a leak in any of the intake hoses or vacuum lines. You might want to do a fuel pressure test. Odd that it only does it when cold. And, at this point, the injectors come into question as well.

No lean codes, just the misfires... I’m really not sure what it could be at all. I remember this happening last winter once or twice, but once I cleared the codes back then the issue went away despite the freezing weather in NY. Now for the last few weeks it’s been on and off again. There is no rough idle when it doesn’t misfire though, so I didn’t think it could be a vacuum leak. Regardless, I appreciate the feedback

[syncrocrick]

Leaking valve cover gasket into the spark plug area?

[upallnight]

intermediate levers? Does the misfire go away after a restart?

[CapeX5]

it's an 01, M62 not N62.

Originally Posted by upallnight

intermediate levers? Does the misfire go away after a restart?

[upallnight]

Originally Posted by CapeX5

it's an 01, M62 not N62.

[Jakal702]

Originally Posted by syncrocrick

Leaking valve cover gasket into the spark plug area?

The valve cover gasket is leaking but I’m not sure. When I changed the spark plugs there was oil on the plugs for the back two cylinders of the bank on the driver side (not sure of the bank and cylinder and numbers)

[Jakal702]

Originally Posted by upallnight

intermediate levers? Does the misfire go away after a restart?

The misfire sometimes goes away after restart but more often than not, the problem persists until the engine is warmed up

[upallnight]

Since you have multiple misfire with fuel cutoff, goes away once the engine is warm I would say that it is not an ignition misfire but a weak cylinder misfire. A weak cylinder misfire is when the cylinder doesn't produce the same amount of power as the other cylinders. The computer can determine this quite easily by the rotational speed of the crank once the spark plug has fired for that cylinder. All the other cylinders could be rotating the crank at 700 rpm but one could be rotating it at 650 or 630, etc... You will not notice the difference but the computer wil know.