Well if it comforts you I had major issues with misfires on cylinder 1,2,3. I was using new plugs and Eldor coils as well. What fixed it for me was switching to B58 coils.
E9X N55E Speedtech 6266 Build
- Thread starter sk8
- Start date
@houtan Thanks for the info. I have the second fuel pump setup on a separate relay. I have tested with it unplugged to to see if maybe the power draw of it kicking on was causing voltage to drop or something, but that had no effect on the misfires. Here's a diagram of how it's wired in on my car.
I have also used ISTA-D to do injector tests, which all passed. I think that test doesn't guarantee that the injectors are good, but I tests for leaks. I'll try to dig around in the software to see if there's any other diagnostics for it.
When I was taking the stock turbo manifold off I noticed cyl 6 having a little more carbon buildup compared to the rest. Even though I don't think I ever got a cyl 6 misfire, I'll probably swap out cyl 6 injector when I do the b58 coils. I have an extra injector laying around since I bough 3.
@SLOWESTN54 I'm really hoping that's my issue. The coils should be here Wednesday, not sure when the NXM kit will come though, don't have tracking yet. I'll be trying pump gas if I still have misfires with the 58 coils.
I have also used ISTA-D to do injector tests, which all passed. I think that test doesn't guarantee that the injectors are good, but I tests for leaks. I'll try to dig around in the software to see if there's any other diagnostics for it.
When I was taking the stock turbo manifold off I noticed cyl 6 having a little more carbon buildup compared to the rest. Even though I don't think I ever got a cyl 6 misfire, I'll probably swap out cyl 6 injector when I do the b58 coils. I have an extra injector laying around since I bough 3.
@SLOWESTN54 I'm really hoping that's my issue. The coils should be here Wednesday, not sure when the NXM kit will come though, don't have tracking yet. I'll be trying pump gas if I still have misfires with the 58 coils.
Hey sk8, 135 DCT with dual lpfp reflex+ setup here. You need a solid state relay to control the second lpfp instead of the hobbswitch. I'm almost certain that the hobbswitch is your issue here. Also I highly recommend you update your DMFW to the S55 one, even on lower RPM it could still throw misfires.
I went with the NOS solid state relay fyi, Get those two things situated and report back.
Got the b58 coil kit in today, and that seemed to fix my misfires, at least in low boost. Plugs are SILZKBR8F8S gapped to 0.026".
Here's a log of a 60-130 run.
I ended up turning the boost up a bit after this run and ran into DSC issues. Had DSC off (short press of the button), and when I did a pull I got codes cc-id 24, 354, and 672. I don't think I was spinning, since it happened when I was in 4th gear ~70mph. Going to make sure I turn DSC fully off for the next runs so I don't run into this issue. Here's a log from when I got the errors.
@onedirty5 Not sure if I'm understanding why the second fuel pump relay would be the issue, do you have any info on why it is a problem?
Here's a log of a 60-130 run.
I ended up turning the boost up a bit after this run and ran into DSC issues. Had DSC off (short press of the button), and when I did a pull I got codes cc-id 24, 354, and 672. I don't think I was spinning, since it happened when I was in 4th gear ~70mph. Going to make sure I turn DSC fully off for the next runs so I don't run into this issue. Here's a log from when I got the errors.
@onedirty5 Not sure if I'm understanding why the second fuel pump relay would be the issue, do you have any info on why it is a problem?
I had issues with reflex+ operating correctly, and couldn't get it to work with the hobbswitch. But now that I come to think of it, it came down to figuring out the correct settings for both the reflex pi tune & dme tune. At that point I was already using a solid state relay.
So if you want to take advantage of pwm capability of the reflex+ unit you purchased/ have the reflex+ control the 2nd lpfp, a solid state relay is recommended.
So if you want to take advantage of pwm capability of the reflex+ unit you purchased/ have the reflex+ control the 2nd lpfp, a solid state relay is recommended.
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Sweet build dude! Look forward to seeing how it turns out when you get it going smooth! Jelly of your E85 access haha
I'm also bamboozled seeing a 135 with a piston style hpfp. Was your car EWG?
I'm also bamboozled seeing a 135 with a piston style hpfp. Was your car EWG?
@onedirty5 Ah that makes sense, a mechanical relay would not work well with PWM. I think you can set it up to be an on/off thing with the RFX and still use a mechanical relay. If you are using a RFX to control the fuel pump, you don't need a hobs switch at all, just one wire running to the RFX. This is what I see in their documentation.
I have a pressure sensor logging my LPF, and not seeing spikes when the second fuel pump kicks on, so probably going to stick with the hobs switch setup until it causes problems.
@azshantris Looks like BMW switched to the piston style in 2013, car is still PWG. Really wish I had the old style, would have been a cheaper HPFP upgrade. I've been keeping up with your build, thanks for posting it!
I have a pressure sensor logging my LPF, and not seeing spikes when the second fuel pump kicks on, so probably going to stick with the hobs switch setup until it causes problems.
@azshantris Looks like BMW switched to the piston style in 2013, car is still PWG. Really wish I had the old style, would have been a cheaper HPFP upgrade. I've been keeping up with your build, thanks for posting it!
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