rcdash

iTrader: (18)

It's not the exhaust manifold bolts. I'm sure those are as tight as can be. You will need to look for signs of an exhaust leak. I recall with the JWT kit, the manifold shield cover bolts right onto the manifold and the holes go all the way through, so if the screw backs out, voila -> manifold leak. Not sure how the AAM kit has the shields attached.

It sounds like you had an intake manifold gasket issue? That could be the problem?

The reason closed loop is failing is because the AFR readings are wacky. The O2 sensors are driving the computer crazy. Somehow extra air is getting "read" by those sensors. Could be leaks right around those sensors...

Milosis

The heat shields tighten down on the manifold bolts to engine block. you slide the shield onto the exhaust studs and tighten the nuts down to secure it in place.

I didn't have an intake gasket issue that I knew of, I retraced my steps on install and that was one of them, I had to remove it originally to install my fuel setup(rails + injectors). I thought it might be where my issue is coming from so I bought and replaced the gaskets on the lower plenum and I have to get another upper gasket for the intake manifold because they sent the wrong one.

I have had to pull the downpipes once to see if my new turbos were allowing oil into the exhaust housings, had a slight smoking issue on deceleration. Turns out its a by product of the AAM kit, tuner identified it right away. They ship an overly strong check valve that can sometimes cause positive crankcase pressure. The turbo downpipes attach via V band Clamps and I've shook them pretty good they seem firm.. Ill climb under and double check as well as take a look at the upper O2 sensors. As far as I know they turn the lower o2 sensors off but ill take a look in uprev to verify.

Milosis

Well I've sent the injectors off to injector clinic. They are all on the new side, less than 3k miles. One of them appeared to have some surface rust near the squirter section but other than that they are identical apart from the individual numbers. Its sad I'm actually hoping I've got a defective injector pushing too much fuel into the cylinder. The alternative is trailering the car up to Z1 motorsports. It pisses me off I cant figure this out!

Milosis

Got the injectors back, numbers are a little surprising for mostly new injectors. All are functioning well i suppose

inj#1 932 inj#2 931 inj#3 941 inj#4 913 inj#5 928 inj#6 914

these are flow rates in cc, i was disappointed they werent closer to 1000cc. But anyway I've reinstalled them with the lower flowing ones furthest away from the throttle bodies. I'll be buttoning the car back up and running final tests before giving up. Looks like i'll be trailering it to Z1.. SMH

Milosis

FINAL UPDATE(ROUGH IDLE ISSUE RESOLVED)

So for everyone who gave me advice thank you so much for taking the time to help me sort my issue out. I've fixed it - here's how

With the Appointment to Z1 Motorsports getting closer I decided to try one more thing( apart from the injector cleaning - maf sensors replaced - throttle bodies replaced - Tune adjusments - Vacuum checking - spark plugs - Accelerator pedal replacement - these things lol). Went on to Nissanunlimited.com and looked into buying a used ECM. Found one with the Same Part number's - and incase anyone needs to know or do a google search I hope they stumble upon this thread. You need to match the first big letter and number along with the next 11 characters. EXAMPLE "M1 MEC100-260 C1" there are four other digits, in my case the ECM part # was M1 MEC100-260 C1 7323. These last 4 digits don't really matter I think. I searched for an ECM same year with M/T and without Traction Control as I have the base model 2007 z. Found one for 90 bucks shipped. A few issues sprung up giving me trouble trying to trouble shoot using a replacement ECM. Biggest issue was the NATS system. For those who don't know its a security system which ties the chip in your key to the ignition / ECM. With it enabled you cant simply plug a different ECM in and start your car, engine will turn over but no fire. Used to be you could disable the Codes P1611 and P1615 in Uprev Tuner edition but unfortunately do to EPA coming down hard on these software providers you can nolonger disable DTC's which would let you clear emissions checks?! Now only the Pro Tuner license has the option. Luckily I've kept in contact with my tuner shops and emailed my rom to them. They disabled NATS and emailed me back. Flashed the ECM, started the car and PERFECT!! Car warmed up around 1800 settling down and down til it reached my target. I let the car idle for 15 min and took it for a drive, some WOT, took it out of gear and it idled right down to target. Turned it off, let it sit a bit, started it back up and idles right at target. So hell yea guys cars fixed!

Now I'm not saying this is your solution should you run into this beast of a f***ing problem. A lot of people jump on the Throttle bodies as the cause. Thing is I never messed with my butterflies, never sprayed cleaner in them. I did a twin turbo install and had it tuned like your supposed to. Maybe starting it up before having it tuned to check for fuel leaks etc is what caused the ECM to lock on the wrong idle data? A UK forum I read said there are two eproms on the ECM board, one to control idle and one for load operation. They said when it gets messed up its not fixable unless you reprogram it and the local Nissan dealership didn't even wanna talk to me because I twin turbod my car so wtf..

So if your car is exhibiting these symptoms, rough idle 1500 - 1800, starting to break up kinda bad under load(the heavy misfire started up on me before id ordered the ECM, thought I got a bad set of new OEM plugs. Turned out to be ECM malfunctioning). You've checked for Vacuum leaks - there aren't many places to look.
You've checked Throttle bodies - if you didn't spray them before they became an issue
You've checked MAF sensors - you can source these easily, other Nissan cars around same year use them
Your issue didn't start right after a tuning session

It could be a faulty ECM. If you think it is and your not using Uprev, unfortunately your only option is to head up to a Nissan Dealer and have them reprogram an ECM(chances are they'll have to send it off unless your shop is the unicorn of shops). If you are using Uprev there is 1 shop in Georgia - Z1 Motorsports, ask for Jon Parnham. And theres one shop in South Florida - Pros Tuning, ask for Roger or Nick. Let em know you've bought a used ECM and need the NATS disabled on your ROM and they'll try to help you out.

eZg

iTrader: (5)

Good info....thanks for taking the time to post.

So wonder how tuners plan initial startups to avoid the possible ECM lockup? Wish I knew more about tuning.