[Cheekrs]

I was doing a little pull entering the freeway the other day (3/4 throttle) and the car immediately sputtered, CEL, very little throttle response, stuttering acceleration the list goes on. Rough idle around 1000rpm bouncing up and down.

I plugged in my MHD adapter and ran a quick DME scan. I have my log below from the scan. I cleared the codes and started up - no CEL, no issues, drove like a champ on the way home however I was too nervous to get on it fearing it would happen again. I had about a 30-40 mile drive home and made it there no problems. It ran like normal.

2011 n55 335i msport 6spd mt MHD stage 1 plus, bms intake, vrsf charge pipe, and most if not all maintenance caught up on. Any input or ideas what could have happened? I’d love to correct anything that may be looming to prevent this from happening again.

Codes:

7/20/2022 4:15:51 PM
- ME active codes
None
7/20/2022 4:15:17 PM
- DME active codes -
2EE0 - Combustion misfires, several cylinders:
Fuel injection deactivation.
2EE2 - Combustion misfires, several cylinders:
Damaging exhaust gas after starting up.
2EE6 - Combustion misfire, cylinder 1:
Damaging exhaust gas after starting up.
2EEA - Combustion misfire, cylinder 3: Fuel
injection deactivation.
2EFE - Combustion misfires, several cylinders:
Damaging to catalytic converter or damaging
exhaust gas.
2EFF - Combustion misfire, cylinder 1:
Damaging to catalytic converter or damaging
exhaust gas.
2F01
- Combustion misfire, cylinder 3:
Damaging to catalytic converter or damaging
exhaust gas.
- ME shadow (inactive) codes
2EF7-DME: Map thermostat, activation.

[Cheekrs]

Bump

[gbalthrop]

Originally Posted by Cheekrs

I was doing a little pull entering the freeway the other day (3/4 throttle) and the car immediately sputtered, CEL, very little throttle response, stuttering acceleration the list goes on. Rough idle around 1000rpm bouncing up and down. I plugged in my MHD adapter and ran a quick DME scan. I have my log below from the scan. I cleared the codes and started up - no CEL, no issues, drove like a champ on the way home...2011 n55 335i msport 6spd mt MHD stage 1...

How many miles on your current set of plugs?

Suggestion:
When you have Fault Codes that have NOT been Cleared (too late NOW ;-), take the time to read/save the "Freeze Frame Data" which is a "Snapshot" of System Conditions (such as Engine Temp, RPM, Load) at the moment a fault code was saved in DME Fault Memory.

That FF Data gives "Clues" as to the cause of a fault. ALL of your Fault Codes are related to misfire, and you had "misfire" on cylinders 1 & 3. If "misfire" occurred at high RPM/Load ONLY, the FIRST suspect is enlarged plug gap, where coil cannot provide sufficient voltage to fire plug 50 times per second at 6,000 RPM.

Since the car ran fine after turning off and back on, as is usually the case with High RPM "misfire", I would NOT have heartburn about doing WOT acceleration in 1st or 2nd (high Speed is NOT needed, just high RPM in Low Gear) at a safe spot (where you can pull over if needed) near home. This time, do NOT clear the codes until you have viewed/ saved the FF Data.

Hopefully a simple/cheap plug change (measure the gap on old plugs if they are of type where gap can change) is all that is needed.
George

[Cheekrs]

Hey thanks for responding - the plugs are likely in need of changing. I got the car with 75k and had no info on when they were changed. Been thinking about trying the “colder” plugs. Any other suggestions?
I’ll definitely be sure to record everything if it happens again.. it’s definitely got me paranoid. I’ll do some local laps and see how she fares.
Thx

[Serf27]

Not sure what mhd stage 1 compares with jb4, but my n54 with standard plugs on jb4 would only last a few months.

Went 1.5 step colder and some dielectric grease and no more random misfires at wot.

Dielectric grease in the coil boots help too.