R56 Mini- Mystery CEL

pjbgravely wrote: In reply to iceracer: Good dry gas is isopropyl alcohol. It absorbs water while still retaining a burnable solution. A cheaper dry gas is menthol. It doesn't remove as much water but it is still burnable. Both have been sold as a water remover for gasoline for a long time. I know that ethanol can suck up a lot of water but as far as I know it has never been sold as a gasoline water remover. I wonder why?

Because the BATF makes the sale of anything with ethanol kinda difficult. If isopropyl or methanol can do the same thing with less red tape, why bother with ethanol?

To the OP, it sounds like you have a boost leak if it only happens under heavy load.

Knurled wrote: To the OP, it sounds like you have a boost leak if it only happens under heavy load.

I can't find any reasons why you're not right. All I can do is take apart the intake plumbing again and hope for the best...

Checked one of the charge pipe connections that's more complicated than a hose clamp. Seemed a little bit dirty, so I cleaned it up and took it for a spin.

Nope.

I'm not getting any codes regarding the fuel system or fuel delivery... Does anyone know if I'd get some fuel pressure codes or something if I had a clogged filter, or something along those lines?

Nope - fuel delivery problems will generally manifest as a lean code - computer runs out of control authority to maintain desired air/fuel ratio. The kicker for THAT is, the fuel system has to get pretty bad since the computer generally only is in feedback control at part throttle. How bad does a fuel pump or filter have to get in order to not allow 30hp worth of fuel to flow?

I was slammed at work today. I promised myself that I'd look up what the BMW code is, see if I can get anything more useful besides a poor German Engineer to English translation. Gotta love Euro cars, they keep all of their own internal fault codes in addition to the SAE codes.

The description sounds like it could be a heated crankcase vent line circuit failed. Which could definitely cause a boost leak if the line simply was left undone. But I don't know if BMW was doing heated crankcase vent hoses in that timeframe. BMWese can be so obtuse, that could mean an O2 heater circuit or IAT circuit for that matter. I promise I'll do some digging tomorrow.

Thanks man, I really appreciate it. I've got the list of codes from the "CarlyBMW" app that has all the BMW specific ones. So far, the descriptions only mention misfires and things of that ilk, but like you said, you never know. Here's the codes it's throwing:

Code: 2EFE Fault: :e-fan / Electric fan failure / Motorluefter / Fan control / Temperature Intake Air / Message failed / Misfire, a plurality of cylinders: detect

Code: 2F02 Fault: :Message failed / Temperature Intake Air / throttle intake / Misfire, cylinder 4: detected

Code: 2EE0 Fault: :Coolant temperature sensor / DFE Failure / Temperaturfuehler Motorkuehlmittel / Coolant temperature sensor signal circuit or short circuit to positive / Engine misfire , cylinder / Pressure sensor, coolant / Sensor Cryogen

Code: 2EED Fault: :Engine misfire , cylinder

Code: 2EFF Fault: :Misfire, cylinder 1: detected / Message failed / Fan control / electric fan, self-diagnosis / Electric fan self-diagnosis stage 1: Light Fan error

Code: 2EE4 Fault: :Engine misfire , cylinder / Kuehlmitteltemperatur-Sensor, Plausibilitaet, Shunt

Code: 2EF7 Fault: :Map-controlled thermostat / Engine misfire: injection shutdown

Several of the codes mention other possible causes like coolant temperature sensor, etc. but I have a hard time believing them since the car runs absolutely fine at partial load. It doesn't have any of the classic symptoms of a failed coolant temp sensor. The last one, "injection shutdown" makes me think the ECU is intentionally cutting fuel because of something it sees.

I'm suspecting, from the descriptions you were given, those code numbers are generic for BMW and your app isn't smart enough to tell which codes correspond to which controllers.

I suspect you're right. I'd like to avoid paying someone with a real scanner to figure it out, but if I can't, I might have to. We have a guy that comes by the shop to do BMW coding work occasionally, if we have him come out for anything else I may just bring the car out to the shop and provoke some codes.

Would a narrowband O2 sensor show a fuel starvation problem, if that's what was causing the misfire? Watching an O2 sensor readout on a Torque app graph, it's showing "rich" when it's misfiring.

unevolved wrote: Would a narrowband O2 sensor show a fuel starvation problem, if that's what was causing the misfire? Watching an O2 sensor readout on a Torque app graph, it's showing "rich" when it's misfiring.

If you have a misfire caused by lack of spark then I would expect to see a rich pulse. I would assume that a lean pulse would be caused by fuel starvation.

If the car does not ignite the air/fuel mixture and it goes out the exhaust valve, any type of O2 sensor (wideband or narrow) will show a lean condition. Remember the sensor is looking for oxygen content, doesn't matter if it's dripping with fuel, it'll see the unburnt oxygen in the exhaust stream.

I guess a better question... Is a narrowband useful enough to notice a misfire? I feel like one cylinder stuttering a handful of times at 4-5k RPM may not get noticed by an OBDII scanner reading at what, maybe 10Hz?

unevolved wrote: I guess a better question... Is a narrowband useful enough to notice a misfire? I feel like one cylinder stuttering a handful of times at 4-5k RPM may not get noticed by an OBDII scanner reading at what, maybe 10Hz?

It's not the O2 that determines which cyl is misfiring.

It watches the crank and possibly cam sensors to see how fast the crank is turning for every half-revolution. If one half rev is considerably slower than the others(due to the combustion not propelling the piston as quickly as it should), it will set cyl X misfire code.

flatlander937 wrote:

unevolved wrote: I guess a better question... Is a narrowband useful enough to notice a misfire? I feel like one cylinder stuttering a handful of times at 4-5k RPM may not get noticed by an OBDII scanner reading at what, maybe 10Hz?

It's not the O2 that determines which cyl is misfiring. It watches the crank and possibly cam sensors to see how fast the crank is turning for every half-revolution. If one half rev is considerably slower than the others(due to the combustion not propelling the piston as quickly as it should), it will set cyl X misfire code.

Very interesting, thanks. I was wondering how/why it knew which cylinder was missing.

I was hoping the O2 readout would help me determine if it was a fuel issue, or a spark issue, though. I still haven't figured out what's causing this issue. All the computer will tell me is that it's misfiring.

Can you watch any datastream items while running/misfiring?

Watch coolant temp, intake temp, fuel trims(long and short term), MAP sensor reading, and if it has it, individual injector pulsewidths/duty cycle while its misfiring.

Also have you checked the PCV system?

Run it at idle, pull the oil fill cap off. It should have a very LIGHT vacuum. If its ridiculously stuck on from crazy vacuum you need a new valve cover(integral PCV). NORMALLY you get a lean code with this though.

It sounds like its either misfiring under high load and/or boost.

I'd recommend you beg borrow or steal an EVAP leak testing machine. Put a rubber glove over the intake tube(preferably as far upstream as possible) and pump smoke into the intake via where the vacuum line from the purge solenoid normally goes.

To clarify: is it misfiring on multiple or just cyl 2 now? Does it feel like all cylinders are contributing or is there a single dead miss(normally pretty obvious).

Have you changed the plugs to rule that out?

Finally solved it! Ran a bunch of fuel system cleaner through it, which really helped.

Drove it to a dealership and traded it in on a 2007 Rav4. Problem solved!

unevolved wrote: Finally solved it! Ran a bunch of fuel system cleaner through it, which really helped. Drove it to a dealership and traded it in on a 2007 Rav4. Problem solved!

I'm almost there myself but we already have a RAV4...

Yeah, I highly recommend not owning an R56 LCI now. It's great. I'm so happy I made it through a phase of Mini ownership without ever having to change that serpentine.

Best part is, I get my 4Runner back!