[Chirho1987]

Hey all,

I have been chasing a minor issue since I installed catless downpipes. Initially, I had a rough idle that would kind of wobble the car and would want to stall the engine when I was coming to a stop. Since then I have installed ngk iridium plugs and eldor coils. I also got a stage 2 tune from mission performance and stage 3 trans tune from xhp.

Once everything was installed and flashed, the car ran smoother. It no longer felt like stalling and had very good performance at first. Later, the car would have a little power loss/hesitation when I was WOT. No codes were thrown or CEL. If I let off the throttle and get back on it, the car continued to accel just fine.

So here is my issue and my thoughts. Adding to the power loss/hesitation, if I turn the AC on at idle, the rpms fluctuate and I can audibly here it, fluctuates between 650-800. If I turn the AC off, it idles fine around 600-650. I did notice the the air intake was loose where it connects to the turbos. Both of them were broken at the screw and not tightened down. I figured vacuum leak. I purchased new ones and was able to install them and tighten down everything. Then I noticed the plastic clips that attach to the air intake from the PCV system were broken. Again another vacuum leak. I replaced those with new ones and orings. I checked the rest of the pcv and saw no leaks. And yes, the previous owner had all the plastic tubbing redone to rubber for the pcv.

Despite all then new parts and such and checking for vacuum leaks, i still have the fluctuation. I decided to check the new plugs and coils that have about 3k miles on them at this point. 4 of the 8 plugs are pretty black but none of them are white tipped. I also noticed the the eldor coils did not seat all the way into the plug hole. There is a gap near the top where dirt has been able to get in under the rubber seal.

I have heard that Eldor coils fit the N63 engine but they do not fit the N63tu engine that I have due to a different bore hole design after the upgrade.

I know I have been rambling on, just wanted to get all the info out there and what I have done so far. So now the questions.
1) Do the Eldor coils not fit in the n63tu engine? I am ready to return them asap.
2) Is the AC and idle fluctuation normal despite never having it prior to engine mods?
3) If eldor coils don't fit correctly, is that what is causing the power losses at WOT? or is that the HPFP? (more info I forgot= I did have a DTM while racing an Audi, I still won, and the code was bank 2 fuel pressure was too low/ lean)

Thanks in advance for any advice/info.

[Dking078]

I had a somewhat similar scenario with high throttle situations. Normal day to day was totally complaint, but 60%+ throttle moments under load it would feel like the car was cutting out.

I was only able to force a CEL (and limp mode) if I forcefully made it hesitate in that range a few times. Came up as misfires and fuel cutoffs.

Initial thought was freak 14-15 Fuel Injector "Recall". But given the mileage I played the coil swap game, and waddayuhknow. misfires followed.

I had read up on the Eldor situation, and it seems that it only applied to the N63O0 (not TUO1) hence why some M owners used them too. Nothing is really posted about eldors for TUO1, maybe a snippet I saw mentioning your issue. I6 owners had it easy but not 14+ 5/6/750i owners.

I ended up with full Bosch (The Romania thing seems to have blown over) and purrs like a dam kitten at idle and WOT without issue.

If you have a stored code for the fuel trim levels, go to BMW as the pumps are under the "Recall" for 14's. At least in my situation it was more, one day the pump worked, the next it straight up didn't. Terrible idle, etc.

[Chirho1987]

Originally Posted by Dking078

I had a somewhat similar scenario with high throttle situations. Normal day to day was totally complaint, but 60%+ throttle moments under load it would feel like the car was cutting out.

I was only able to force a CEL (and limp mode) if I forcefully made it hesitate in that range a few times. Came up as misfires and fuel cutoffs.

Initial thought was freak 14-15 Fuel Injector "Recall". But given the mileage I played the coil swap game, and waddayuhknow. misfires followed.

I had read up on the Eldor situation, and it seems that it only applied to the N63O0 (not TUO1) hence why some M owners used them too. Nothing is really posted about eldors for TUO1, maybe a snippet I saw mentioning your issue. I6 owners had it easy but not 14+ 5/6/750i owners.

I ended up with full Bosch (The Romania thing seems to have blown over) and purrs like a dam kitten at idle and WOT without issue.

If you have a stored code for the fuel trim levels, go to BMW as the pumps are under the "Recall" for 14's. At least in my situation it was more, one day the pump worked, the next it straight up didn't. Terrible idle, etc.

I put my old Bosch coils back in. I still have the idle fluctuation but those coils are old as hell. At least I know they are seated on the plugs correctly now. I haven't been able to go WOT to see if I have the same issue. Just changed my engine oil and transmission oil so I am taking it a bit easy atm (first time changing both on this car).

I am going to be sending the eldor coils back and getting new Bosch ones from FCPEuro. I also noticed that the pcv system may have a very tiny Crack right where it exits the top of the valve cover. I noticed when switching coils, that there was dried oil around that area as if it sprayed out or something. I'm assuming this could be causing my idle issue?

[EL Jeffe 5]

My 2013 been doing this for years yet no issues no check engine.
I notice my car does this more often during fall season believe it or not or I just might be going crazy. If you do find out let us know