488 Misfires under acceleration over small bumps / rough roads

I've had my car for over 3 months, got it brand new and I've noticed since the first day I drove it a particular behavior when driving over small bumps or rough roads.

When driving at highway speeds on a clear and dry day I notice the cars jolts a bit and looses power for fractions of a second when going over the highway concrete slabs where the pieces connect (Feeling is very similar to going over a patch of standing water on the highway). At first, I didn't pay too much attention to it, I kept experiencing this over rough or bumpy roads, specially under hard acceleration, but in my mind this was simply the traction control cutting power.

Today, under hard acceleration over a bumpy road I felt the car loosing power and the check engine light turned on so I started doing some tests to try and troubleshoot the problem.

I'm not 100% sure if this is my car only or all 488's experience this, but if you try to accelerate hard over irregular bumpy roads the engine will misfire and the check engine light will turn on. I've already disabled Traction (and stability control) completely, to rule them out, but still experience the problem.

The code I get every time this happens is "P338F". I was able to clear the code, but I can easily reproduce it, at least in my car.

Is this a known problem? sounds like an electrical issue. A problem with a ground connection of sorts. But on a brand new car? anyone experiencing something like this or know of someone who does?

 

Also a 488? in your case did you had the problem all the time or like me only under acceleration over rough/irregular bumpy roads? do you remember what what the fault code. was it also P338F?

I'm clearly taking it to the dealer, but I'm documenting everything on my own first so I can explain the problem as best as I can to the serviceman, including riding with someone from the dealer so I can show them how to replicate the problem. Car is only 700 miles!

I've been searching online for the code and seems to be an electrical issue of sorts, most likely a wiring problem with ground either with the ECU or some other component. I've filmed the dashboard when the loss of power occurs and there is no evident loss of brightness in the instrument cluster so whatever the problem is it only affects the engine management computer and not all the electrical systems in the car.

The reason i'm documenting everything is because this is the kind of problem that turns into a nightmare. I'll keep updating this post regularly in case someone ever runs into the same situation with a 488

 

UPDATE: Issue was solved. It was an electrical problem caused by hard-wiring a dashcam via fuse tap to a 'fuse' that (according to the manual) was not 'assigned' to anything, but clearly (if you see the attached diagram) was between fuses assigned to the 'injection' system.

Completely my fault for suggesting that particular fuse to the installer as I believed nothing was going to be affected as the manual shows nothing there


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