[J-Pizzle]

Any 550i owners run into issues with the check engine light coming on for a few days, then disappearing. This has been happening over the last year or so for me. I brought into the dealership and had some of the extended warranty items fixed including te HPFP and injectors, but I still getting this intermittent on and off of the check engine light. The dealership can't seem to narrow down the issue definitively. They had the car for 3 weeks at one point.

Some symptoms I have noticed is slight hesitation on startup (including after automatic stop/start) and sometimes a rough engine when accelerating hard (after car is up to temp). It was noticeably better after replacement of the HPFP, but now it's coming back.

Have any of you gone through this exercise? I'm heading back to the dealer to see if some of this is related to the extended warranty items, but I would like to give them some direction if any of you experienced and have solved this gremlin. Is this concerning and a sign I should be moving to the G30?

My 2014 has 74k miles on the odo.

[Qsilver7]

The CEL is less about the engine and more about the car’s emissions system. So you waiting for another 550i/n63/n63tu owner only narrows the help from fellow forum members.

When you take it back…and they pull the DTC (diagnostic trouble code)….post back what the code is. It should either be the BMW hexadecimal code…from BMW. If you have an OBD II scanner/reader…pull the 5 digit generic DTC (which is part of the OBD II mandate). If you don’t have a scanner or don’t have access to one (friend or family) you can stop by any auto store (like Autozone/O’Reillys/Advanced Auto/Pep Boys/etc) and they will pull the codes for free in every state except California & Hawaii.

The code will tell us which sensor set the fault code and what emissions system it it related to. The problem will be something upstream or downstream from the sensor that set the fault code.

There’s no way anyone can tell you why the CEL (check engine light) came on without the DTC. There are too many areas that could have caused it…the DTC will point us in the direction of what caused the light to illuminate.

Once a fault code has been made…it goes into memory…so it can’t be erased even if the light went off as the system rechecked to see if the issue was still there. And disconnecting the battery and other tactics will not erase the code.

Take note of the 3rd & 4th bullets in the info below about OBD II…and you can see the DTC chart which shows how to breakdown the generic 5 digit “P” codes.