OP, pull the boots off the coils and check for cracks. Also lets see both ends of the plugs. I would lean on injector, log afr you want to see what it is doing just before the misfire. Misfires will cause false leans because of the unused oxygen in the exhaust. I will bet the fuel smell is do to the unburnt fuel as a result of the misfire. I do not run those plugs and and great luck with Bosch FDPOR5.

 

I just went through a similar issue. Even though the symptoms might not be identical to yours. In 2013 I had a RUF issue phisically "worked on" by a US Tuner in order to accept said Tuner's 91 octane tune and injectors. The car ran fine for a while and then PO205 landed, accompanied at times with various misfire codes PO300, PO304 PO305. I had the injector # 5 replaced with a new one. Car ran fine for a while, 3K + miles and then the fault code cycle started again. Wiring resistance from the DME plug to the injector # 5 plug checked OK, so did the "old new" injector. I must add, that for the nearly four years I ran the car on the RUF ecu, I had never seen a PO205 code. After talking it over with a local P mechanic who had had an instance of a GT2 a few years back with similar symptoms, I finally purchased a new DME, had the dealer code it and low and behold after downloading the tune onto the new unmolested ECU, the car has been running fine with no more codes. Early days since I have less than 20 miles worth of driving. I will drive the car all week, 100 + miles and report back next weekend.

Hope this helps.

 

^ yeah, as steve mentioned this also reeks of scpongers issue very deja vu like. needing a new ecu would suck, unless it cured the issue. i guess if it were me, i'd rule out the injectors 100% then go straight to the ecu. merry xmas sheesh...

 

the good thing is used dme computers run about 700$ vs 3000$ for new. theres also a shop that can look over the old unit for damage and repair it if needed

 

really? the can "recover it" so to speak? never heard of that, although this is the absolute main reason i don't even wanna touch my archaic cargraphic tune!

it ain't broke!

 

not the tune but the circuit boards. if theres damage they can fix it up to a point.

 

absolutely, I have a guy who does 'deep' electricals for me, have no problem fixing soldier joints and similar on the boards, but when it gets down to chipset issues they go to him

 

understood, i was trying to make the point that accessing the ecu whether by flashloading or however tunes can/are loaded will or could impact the ecu eventually. but i don't know enough obviously about how they work. but all that flipping files and multiple tunes, that has to bring with it the potential for issues. one would think.

 

I purchased a used ECU from a 6speedonline board member. Unfortunately for me, not him, after "my Tuner" traded immobilizer codes between both ECUs, it turned out to be unusable. The engine would barely fire and throw all sorts of codes I had never seen on my car before. Save your self the heartaches. And if you do like I did, $3K+ for two ECUs is about right. One brand spanking new one from Mr.P is no more than $2600. I know ouch.

 

it's as you know not uncommon for guys with 997t's and probably the 991 by now to have backup ecu's with the stock file for their cars esp while still under warranty. but they aren't in the cheap seats, if ya know what i mean. 2600 i'd be PISSED.

 

This does feel very similar to my issue, although it was a different code. We replaced everything under the sun and finally after the better part of 2 months, we replaced DME and it fixed everything. If you have access to a shop or tuner that has the technology to reprogram a DME it may be worth trying. I have been told that 996 DME failures are becoming more common.

 

proefi baby!!

 

today's fix, BMW LCM...point here being sometimes the fault is obvious(easy 'fix' today), sometimes it's not...

 

Update : Received new 72lb injector from EPL and swapped it into cylinder one. I wouldn't call it the most fun i've had on a weekend but it was close...

The stuttering is completely gone and the car is back to running CEL free and smooth. While I was in there, i replaced the fuel filter so there is a possibility it was that as well, though the one that was removed didn't look awful.

The install wasn't GODAWFUL, but it wasn't fun either. There isn't that much to remove, it's just a PITA to remove each piece.

I am only hitting 1 bar (tune should show 1.4) so I believe I still have a boost leak, hopefully from the intercooler hoses from when I swapped all the coil packs around, but luckily I have new forged boost hoses to install this weekend so hopefully that should do it and I can move on with my life.

I"ll keep everyone posted once I get the new hoses on, hopefully that's it and not the gasket behind the plenum. Thanks to everyone who chimed in on this project and helped me out.









I will say that the 1" or so vacuum line is connected to the plenum (coming out the right side of it) was a bear to get back on the plenum 100%. it's maybe on there 50% but not going anywhere and the clamp is on tight.

 

Glad you have it figured out! Modern injector issues are pretty damn rare, any diagnosis of why injector isn't good? Foreign matter, burnt solenoid, etc?
Cheers,
Rob