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out for a tame Sunday drive, pulled off the highway exit and thought i had a flat tire as car was shaking so bad. looking over everything CEL is on, pulled over, stopped and started a few times, engine running terrible
limped home (all temps stayed normal, no smoke). pulled code P0304. says its a misfire on cylinder 4 (according to internet and my cheap OBD2 scanner).
on the way to the dealer, hope this is nothing serious.
Hopefully it is just the generic misfire issue that a number of these vehicles had early on.
There is a service campaign out that addresses this - assuming it's just the misfire detection and not a real problem with the cylinder.
It is just a firmware update. It also comes with an emissions document confirming the update has been completed and which can be filed if necessary when you renew you registration. I suspect this will be required for Kalifornia but will find out soon when my renewal is due.
My car threw these codes occasionally. They did take the car in and do a full set of diagnostics as directed by Germany and never found anything wrong. In the end I think they just swapped around injectors and recalibrated them and the code went away. Did have one recurrence a year later. I reset the code and it hasn't returned.
Took my car in for the service campaign several weeks ago. Have only driven the car a few times since then but it seems to me that the low speed off-idle drivability in comfort mode when the motor is cold is a little more herky-jerky. May be better when it is fully warmed up, but I haven't actually driven the car enough to confirm that. In Sport+ and Race mode when moving the car still seems to run fine.
Thanks for the info. mine for sure has some issue, it would barely accelerate, and when trying to accelerate, it was vibrating badly.
at idle, it sounded as if it suddenly had a big cam. as it was running so rough. in the shop now... so guess we shall see
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