[Nfifty1vic]

I own a 2008 328i e92 N51 Sulev. I keep having these codes pop up for cylinder 1 and 5 Misfire but never actually had a problem with the engine except this one day when my engine shook really bad as if it was dying down, notified me saying "Engine Malfunction, Reduced power" I took it to bmw stealership, and they "solved the problem" but few days later SES Light turned on once again. I paid 500 for having aftermarket Bosh spark plugs and they weren't even the problem to begin with. I really need help! Any recommendations or ideas?. I've gotten all my spark plug changed, coil pack looking good still, and they also fixed my fuel injector which was leaking on cylinder 2. Thank you

[gbalthrop]

Welcome to the Forum! Please read beyond the sarcasm below.
So a Dealer charged you $500+, allegedly to "Diagnose (properly) and Fix" the misfire issue. They had your car and had the opportunity to run proper "Diagnostic Software" tests with INPA or ISTA, and yet did NOT "Fix" the issue. HOW do you expect folks on a Forum to actually help you SOLVE the issue with NO Data, ONLY a "Vague History"?

If you have access to a Scan Tool that can: (1) read and clear Fault Codes in the DME (Engine Control Module), (2) Read "Freeze Frame Data", which is a "snapshot" of engine conditions such as Temp, RPM & Load & mileage, at the instant the Fault Code was saved in DME Fault Memory, and also (3) Display "Live Data" (Helpful, but Optional), then perhaps we can actually help if you answer the questions below.

If the "Misfire" events do NOT normally result in VERY rough engine performance & idle for ~ one minute, or until you STOP engine and restart, then those events are intermittent misfire, significant enough to cause the SES to light and a "Misfire" code to be saved. HOWEVER, if the "Misfire" occurs long enough on one cylinder, the DME will "De-activate" the Fuel Injector on that cylinder, to prevent unburned fuel from being dumped into the Catalytic Converter on the Cylinder Bank, and it is Injector Deactivation that causes VERY rough running.

Also, the Dealer should have given you an invoice that itemized services performed. If you do NOT have an itemized invoice which describes what tests were conducted, what Fault Codes were read, and what components were replaced (with parts cost identified), then Please Request such an itemization. See if they can attach a jpg or pdf of the invoice to an email to you. Attach that itemization, or scan of paper invoice, to post here.

So if you want to try to solve the issue with Forum help, please answer the
following questions. If you don't want to be bothered, I hope you are able to find a reputable Independent Shop (Indy).

1) If you have access to a Scan Tool or Diagnostic Software, please identify the Make & Model.

2) Can it read & display "Freeze Frame Data"?

3) If you are you able, please attach a copy of any Invoice/Itemization you have from Dealer?

4) What Fault Codes are NOW read in DME Fault Memory & what FF Data for EACH Code?

5) If Very rough running occurs and SES light is lit, does STOPPING Engine and restarting allow normal operation, with NO SES light?

6) Does SES come on ONLY when RPM > 5,000 RPM, such as in WOT acceleration in 1st or 2nd?

7) Do you have access to a Multimeter? A cheap $7 unit from HFT is all you need:
https://www.harborfreight.com/7-func...g_q=multimeter

George