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Sorry to hear this... I have to believe you are dealing with something simple at this point. Everything internal is new and I'm guessing the DME is just getting some bad data somewhere, perhaps there is still a problem, but I'm guessing it is minor at this point. You are on the home stretch. Good idea to check for a bad cat. If you swap the O2 sensors between cats (remember they are different pre and post cat), do the misses follow? I bought new O2 sensors on Amazon for about $70 each. Also might make sense to unplug the MAF in case that is feeding DME bad data... safe to drive without that, without the MAF it shouldn't cause misfires, but it won't run 100%... at least if the misses continue you can rule that out. In addition to possibility of exhaust being plugged up, maybe the intake is plugged up... Did you idle the whole time or did you go through the revs, if you idled, perhaps your IACV is bad (ohm it out), and is causing air starvation (opposite problem or intake leak, and rich running). Or maybe air filter is clogged/etc causing rich. It is also possible there is still a bad vacuum leak somewhere causing lean running. Example: brake booster, SAI, FPR, EVAP purge valve/line, AOS line, AOS, etc. etc. etc. Did you install a new AOS? Flashing CEL with emissions misfires are not good, want to keep from running the engine as much as possible. I guess another possibility is variocam in bank 1, but without any variocam codes I would not look there first. It sure would be nice to have a Durametric, then you could compare values to set points. Maybe take a few days away from it, clear the mind.... Come back and it will be more obvious what is wrong. I had to do this a few times during my rebuild.

I used a brass hose repair kit coupler from home depot for a couple bucks. Works great.

Nice work. I could be wrong but I think it goes up. That being said, on this particular gasket, I don't think it would matter which way you have it.

A pain to do on jack stands isn't it. I use about 3-4 5-gallon paint buckets and just have them ready to put under anything that decides it wants to leak. The paint buckets are nice because when you are done you can put a reusable lid on them to keep the cats and dogs from getting curious. I loosen some of the hoses with the bucket directly underneath. (wear safety goggles) A few smaller buckets always ready to catch smaller drips. For the really messy jobs, I have a shallow 3' x 4' clear storage tub that I put under the entire engine or wherever it might be leaking from. ON a lift you'd have telescoping catch basins that you can move up and down, and they are on wheels and attached to a self contained or remote basin.

Many times the pins are universal, in fact you could even buy them at Napa auto /etc. With the proper pin extractor, it is certainly possible to extract the pins from the existing plug and reinsert them. If you are really careful it is even possible to separate the wires from the pins and re-use the pins on new wires. Any reputable repair shop can and often need to obtain parts on their own, so yes it is possible but you could certainly ask your mechanic... In some cases it can be easier to skip the middle man...

Great post

There are many gaskets not included in that set. Head gaskets, exhaust manifold gaskets, those intake riser gaskets, among a few others are not in that kit. I literally went page by page in PET and recorded every single gasket, oring, and wasker and ordered them. I ended up with some i didn't use but if i found one on the engine I took off and didn't order it, I ordered one and replaced the old. Unfortunate the Porsche kit doesn't include all the gaskets, it would make life so much easier.

Doug I got it covered... a few posts up... p/n 996 110 103 50, metal gasket between intake riser and head.

I bet you anything if you take that info to a V dub dealer parts counter and show them a picture of what you want they could produce a new plug, connector, and pins for you magically (under their parts desk they have rapid prototype machines). :-) Good work!

Sorry Raxo, I don't believe the info on how to do what you are after is publicly available, and if it was, it would be considered an infringement of international copyright held by Dr. Ing. h.c. F. Porsche AG. Secure access to the DME is protected and I believe required to get what you are after. That being said, for a paltry sum of $1,000,000,000 USD I'm sure Porsche would be willing to license this information to you. Furthermore, if it was available, it certainly would not be posted on this board.

Yes qty one between each riser and head, a metal gasket. Part number 996 110 103 50 and number 25 in the pic below... http://www.autoatlanta.com/porsche-parts/996-99-05/107-10.php

Depending on the connector/plug you can get them at a dealer. There are often part numbers written on the connector itself, which if you post here someone might be able to help find a source for the parts. Or you can even go to your Porsche dealer with the part number and they should have a "tech connector kit" that has all sorts of these plugs and connectors and pins or at the very least can order one for you from atlanta or germany. A dealer will probably not splice into an existing engine harness if that is what is required. They probably won't have the tools to extract the pins from the existing plug. In the case of the 996, it turns out the part number cross referenced to many other mfg cars, and it turned out Mercedes price was the best. :-)

On my 996 I was soldered in a new section of wiring to the existing harness and used a brand new connector/plug for my MAF. One of my wires was suspect a few inches up from the maf which is why I spliced in new wiring. It works perfectly after 1 year and 5000 miles. The solders are staggered and shrink-wrapped, and the original shrouding retained make it look like stock. The connector/plug part actually came from a Mercedes dealer and IIRC it cost around $30 for all the wires, pins, and the plug. I would expect to pay an independent shop 1-2 hours of time to do the soldering job. So yes, it is totally do-able without replacing the entire harness, given someone with sufficient soldering and electrical skills. Another alternative on some connectors is you can just replace the pins and plug itself, and in some even just remove the existing pins given the right tool and then insert them into a new plug.

+1 to checking fuel pressure and for quantity. The harbor freight A/C manifold kit works perfectly for both functions and is cheap. When you say you got misses when spraying around the FI area, did you install new orings and gaskets for the intake riser and manifold? Did you use the correct torque and new micro encapsulated bolts on the manifold and risers? +1 to dropping the engine to do the injectors. The problem with doing it from the top and removing all the intake is you risk introducing more intake leaks! (been there done that when I did an AOS, not fun). I believe any of the M96/97 injectors are backwards compatible. I think I remember reading the newest ones available on engines up until they switched to DFI will work, however I can't recall my sources. I also remember rt.org member 1999porsche911 who used injectors that were not porsche specified (read HIGH flow), and his car ran fine, although I think he was also running a few pounds of boost. ;) FWIW, I'm running one generation below the latest (they are white colored) and they work perfectly. I think the only difference between those and the 3.8L ones are flow rate. The white ones are the injectors designated for the 3.6L and my TRA are quite steady around 0.97 for both banks. The new design is slightly different than the original. The 996 MK1 clips will not line up to the new style injectors without modification to them. When I installed mine I thought that it was important to retain the clip to "hold them in place", however I later saw an engine where this wasn't done and they were just "floating" for lack of better term (but they were all installed at the same depth). Well they actually would not float if they are seated. What I believe is important is that they are all installed the same way (either all the way down or all the way up, and they are fully seated), dont forget to lube the orings, I used tire sealant IIRC. Mine are all the way 'up' and clipped in as you see in the pic below, and I've seen them installed all the way down with the clip just used as a "spacer" without any modifications. Both engines perform flawlessly. As you can see I dremeled small slots above the existing slots so that they would fit around the injector and the flange on the rail. Edit: and forgot to mention the new injectors don't have those fiddly plastic guides to worry about.

I'm hoping you put in new plugs too? I would guess random misfires on both banks could be due to manifold leak or injectors or fuel delivery problem or all three. Sure other stuff is possible but it sounds like you sorted most of the mechanical stuff out already, and have new rings, new pistons & cylinders, and the timing is good.

It sounds like you're having mises on both banks. I never had misses with mine but I certainly had very poor running with the old blue injectors and I didn't run the engine very long at all like this. They were not sized correctly for the larger cylinders (not to mention Porsche very quickly replaced the orig blue ones with the green ones (better spray pattern) before moving to the white ones shortly thereafter). And even still a replacement came later for the white injectors... This is a guessing game and just spending your money for you without your fuel trims, and without verifying you don't have any air intake leaks using a smoke machine but.... I would think with the right size injectors and fresh injector orings that prevent air intake leaks around the injector ports you can safely tick those off the list. Old injector orings that don't seal = an air intake leak. I didnt take the chance with my rebuild and replaced every single seal and oring on the engine. Didn't skip any of those, including with my old injectors when I had installed them, they even got new orings. Of course, even though they were sealed well, they were still not sized correctly and the injector time was higher than it should be as I verified with Durametric. Air intake leak or too small fuel injectors or both they are both going to show up as the DME adding more fuel and the engine is going to run like crap when it is running LEAN.

LOL mike. More like 13 year old brittle heat cycled plastic... of course the new white injectors dont have these plastic parts, they are all one piece.

It helps to remove the throttle body and T-tube behind it to access the cable mentioned in the previous post. DO NOT drop anything in the intake. Put duct tape or something over it while you are working on top of the engine. Yes autozone or most parts stores test alternators for free, with a fancy report.

Oh, sorry injectors are a PITA to replace with engine in car... (read probably darn close to impossible without dismantling the entire intake) ask me how I know.... Here's how low I had to bring mine (and a little lower would not have hurt) Oh and did I mention here's a good reason to replace old injectors (notice the crack?) BTW these were professionally cleaned with new orings... bad idea! Should have just replaced them from the beginning like I did with everything else. Cutting corners just adds time and headache and money. THis is what I found when I removed the injectors after just a few hours on the rebuild motor...

Good idea. Bad injector orings can be an intake leak. Bad or under sized injectors can also cause a problem. Dont forget to lube the orings.

If the misfires move that might be a good sign towards vac leak or something affecting both sides.

Also when was the last time you reset the ecu, maybe it learned some really bad habits for when you had major variocam issues in the other bank and the clogged fuel filter. Although... it should be fairly quick to learn values that are way off... maybe more wishful thinking.

Misfires on all cylinders in one bank could be variocam or valve train related. Spring, lifter, actuator, solenoid, timing, etc. Wishful thinking, but maybe a clog in the fuel pipe for that bank, although since the connection for bank 2 goes through bank 1 first I would tend to think bank 2 would also be suffering. Any other codes or just the misfires?

This sounds exactly like a problem I faced, and in my case it turned out to be bad primary wires on top of the engine. What solved this problem on my car was replacing the large main that goes from the alternator to starter to primary jump point in engine. That wire can become corroded, and is a well documented issue here and elsewhere. http://www.renntech.org/forums/topic/31797-strange-low-voltage-problems/ Any improperly tightened primary battery wires can deplete/damage an electrical system's capabilities in short order. ALSO clean contacts and/or replace the primary ground strap from the body to engine near the RHS rear wheel. That being said, there are are many possible culprits. Certainly on the top of the list would be battery, alternator, and regulator, as well as wiring.

+1 to PIAA Richard!