[Nick8375]

Hi all, have been slowly trying to figure this car out. First was a leak at the turbo inlet, which I fixed. Thought that was causing my misfires. Was not. I then started getting code U3003 for “Bad Voltage” I had the battery tested and it was fine. (Note when they tested the battery it turned on normal for the first time, and there were no codes for about 5-10 mins and a stable idle for the first time) I ended up swapping it out what my other car (same battery) hooked it up and it is still misfiring. But now with a smaller selection of codes. P0301 misfire, the code for running too lean, then this U30FO code. I need to go drive it again to make sure but it was random misfires before, especially 1 2 and 3.

Anyone have any suggestions? I was smoke testing the intake system and did not find a leak besides the inlet but after fixing that I was not able to locate any other leaks, and the smoke was filling the glove on the other end of the intake. Any suggestions would be greatly appreciated, thinking about just taking it to the dealer but would really like to avoid those costs.
Redownloading INPA tonight and going to try and read the codes from there. Struggling to operate the software though as there is so much going on.

Car runs and drives still, you can feel the power loss when it misfires. I don't think it is a boost leak as it feels like full boost when it's not missing and running smoothly. but I might be wrong about that honestly. Starts a bit rough at times too

Another thing I noticed at high RPMs or whenever I gas it hard, the fuel gauge will drop all the way down to empty and go back up after a second. At around 5-6k rpms rpms in the manual mode, the hazard lights turn on solid on the dash until you upshift.
Thank you all!

[gbalthrop]

Originally Posted by Nick8375

... codes: P0301 misfire, the code for running too lean, then this U30FO code. I need to go drive it again to make sure but it was random misfires before, especially 1 2 and 3... Redownloading INPA tonight and going to try and read the codes from there...
at high RPMs or whenever I gas it hard, the fuel gauge will drop all the way down to empty and go back up after a second. At around 5-6k rpms rpms in the manual mode, the hazard lights turn on solid on the dash until you upshift.
Thank you all!

There appears to be a K-CAN communication fault which is causing bogus information on the Instrument Cluster/KOMBI. ALL of the Instrument Cluster displays (including the fuel gauge), EXCEPT the Ambient Temp, are via K-CAN Bus, instead of "direct" or "hardwire".

We need to know Fault Codes in ALL Modules, or at least in the DME & KOMBI modules. I attach a pdf: "INPA Tutorial Quickstart" that explains the basics of reading Fault Codes in ALL Modules, using "Functional Jobs". The pdf also contains sample screens from my 3/2007 build 328xi, and some installation tips. Don't let the German scare you. We, or Google Translate, can help you with that. There is a LOT more detail related to Fault Diagnosis than is covered in this PDF, and if you are able to get the Functional Jobs codes, then we can go to "Next Step".

If you can't get INPA to work, please do the following:

1) Describe what issues you are having, attaching ScreenPrints of any error messages, and what menu selections were made to have that screen appear.

2) Although it would be MOST helpful to get INPA working, you can get Fault Codes read (at least in DME / Engine Control Module & KOMBI Module) at your nearest large parts retailer, such as Advance Auto or AutoZone.

Somehow, you need to get us ALL Fault Codes in those two modules, particularly the Codes related to "Too Lean Mixture". Also, please check the "U30F0" code, as I do NOT find anything for that number. "U" codes are communication errors. Once we have that information, we can suggest "Next Steps".
George