Well my 2012 QX56 loaded with all options is having the same problem. Loss if power and barely gets over 40mph. I have a bumper to bumper warranty covered by GM. They've actually been great but seems they're tired of Infinitis shit too. First visit was ecu, less then a week later 2nd visit wire harness, warranty covers but asks Infinitis to thoroughly inspect all connections and assure no other problems.. exist. Driving home from dealer car has the same symptoms. They say another wire harness. GM warranty says this isn't an open check book and wants dealer to split costs. My car has been in the shop for over 2 months. They gave me a loaner but I'll like to have my car fixed correctly. I had a 2010 Toyota Sequoia Platinum before this turd. Never had a problem with the Toyota. I'll be going back as soon as Infiniti can figure it out.
2012 QX56 - P062B code - Sputtering and loss of power
- Thread starter rbmphillips
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so I think your on to something , I have the same issue its been running poor since I bought it and and I've put a ecu on and like everybody else it ran the same and one day I said maybe it had bad fuel because it could have been sitting for awhile before I got it so I put a fuel injector cleaner in the tank filled it with gas just to see if its because the carbon I let it run for 2 hrs walked outside and what do you know running like she fresh off the line, drove fine, the next day back to square one. you explained so well did you have the same problem on the same truck cleaned it and it never returned? I fill you my be right, this is the only thing that know of the other fixes have in common and the problem comes back, nobody directly address carbon build up.
primov8
Well-known member
I linked this same topic over at CA, P0171/P0300. Fixed.
It's definitely been brought up as carbon buildup is notorious on GDI engines in general. I didn't take pics of the valves when I was working on my Z62 but @pjdavep took the time to take and post pics of how dirty these GDI engines can get.
Did your problem get fixed after cleaning the carbon buildup?
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G-218282
Hi, I have a 2006 QX56 that ran fine about 15 miles last week when it was very cold. I shut it off for about two hours and when I started it up I noticed it had the brake and battery lights come on but was running ok. If I kept the idle up is was fine but if it went down to an idle it would kick lights back on and fans would drop down in speed. I drove it out behind my house and hooked up a trailer three days later and it started doing the battery/brake light again and had gone into a limp mode. I drove it back out to my house, shut it off and it wouldn't even turn over to start. I jumped it and drove it to the shop and charged battery and it was running ok but still had the lights on in dash. I figured the alternator was going and wanted to test output right at alternator. I got a fluxuating voltage and never more than what the battery had. I ordered a new alternator. Should be here next week. Tonight I had to go in shop and could hear what sounded like a small maybe valve making an odd noise(open and closing, or fluttering) somewhere above the alternator area. I dropped the lift down and opened up the hood to see if I could find where it was coming from and it stopped before I could tell. I tried starting it and the battery is dead, not even a click. I didn't even have the keys in it so I wonder what was making the noise. I'm going to charge the battery tomorrow after removing the cables and see how the load on the battery does. After reading about the sensing alternator, I wonder if I tested it right to know or if I'm dealing with a shorted battery maybe. So odd, but after owning this for four years I find that odd electrical is the norm.
Thanks,
Rob
Thanks,
Rob
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I just removed the intake plenum. What is the best way to clean the valves?
pjdavep
Active member
Look at Primov's post #43 and follow the rabbit hole.
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G-926717
I have read this particular form 50 times my car has been doing the past 4 months maybe two or three times a week usually I could turn it off back on and solve the problem but today he decides not to fix itself anymore and I'm broke down in a parking lot in Atlanta. Yes I realize I should have fixed it sooner. Did anyone come up with a solution to this. I have taken the computer, battery out checked the grounds, check the battery connections, brand new battery I'm at a loss and there's really nothing else online. Any help would be greatly appreciated. Also the The fuel system also shows open loop on both banks Don't know what that means
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pjdavep
Active member
Are you in the correct forum thread? You've had sputtering and loss of power for four months, but now can't start it? If you are in the wrong thread and have had issues starting it for the last few months, it could be your starter. My 2011's went out last year.
Later,
pjdavep
Yaeah
Yeah I'm on the right thread usually in the mornings not all mornings just some. I would start the car it starts fine and it then starts sputtering and has no power when you drive like not even enough to barely get you up a hill and the P062P code comes up so I would pull over turn it off and back on and bam the car worked perfectly again. maybe twice a week it would start the same problem, sputtering and lose power. I would turn it off and back on and it would start working again, but now when I turn it back off and on again it doesn't reset itself and I'm stuck with one code P062B. And the car just has very rough idle and very low power. Everything that's on this form I am having the same problems.
pjdavep
Active member
I'd consider Infiniti's induction service. These engines get FILTHY inside. They hook up a drip tube to your intake and run it for a while and it slowly clears all the injector/lifter gunk. It'll cause quite the smoke show. My 2011 even backfired a few times when they did it. They could also hook up a smoker to make sure you don't have any vacuum leaks in the system.
Later,
pjdavep
Later,
pjdavep
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marctronixx
Staff member
agree on the induction service! these DI engines do get carbon-y by their design. i did that twice i believe in the 95K miles i had my 2012 and the idle speed was steady at 800. i never had any fluctuations or rough idle. always used high test petrol too! :d
did you ever get it figured out?
I own a 2011 QX56 and have experienced that very problem. I do my own work and found one of the two camshaft phaser had failed. The phasers are located on the front end of the engine heads. Typically the left side usually fails. This is a problem associated with lack of regular oil/filter changes. You could try adding Seafoam to the oil system and drive for approximately 100 miles, then change the oil/filter as you regularly would. If this does resolve it, look into replacing the phasers. Hope this helps.
pjdavep
Active member
Thanks for posting that. Would you mind referencing the part number? I'm having a hard time figuring it out and I try to do my own work on my 2011 when feasible. Could you have possibly been referencing a VVT solenoid or camshaft position sensor?
Thanks!
pjdavep
Thanks!
pjdavep
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G-735494
I just wanted to give an update on this post I have had this p062b problem for months and I finally fixed it tonight. First off I did a power balance test which I know unless you have a diagnostic scanner you can't do but I wasn't getting any thing from cylinders four and seven. Next I pull the intake manifold and did a continuity test between all the injectors to the EMC they are diagrams out there if you look, then I pulled the injectors all of those were fine, coil packs for fine, and then I looked down into the intake and it was absolutely filthy after cleaning out the manifolds and valves with a brush and basic intake manifold cleaner I fired it up and no more P062B code no more misfire or sputtering and it definitely wasn't the wiring harness. that is what most people told me it was the wiring harness or computer. I replaced the computer and that wasn't it so if you have the P062B code start with pulling the intake manifold and cleaning the valves it's not hard but it's not easy, it's doable for the average person that's knowledgeable good luck.
I had this problem for months. it drove me crazy. I bought i a new ECM and that was not it. i dont recommend buying one. The little i could find online said it might be the wiring harness but i tested the resistance to each coil and everything was fine. so the next step was to take the intake manifold off and check the injectors. i was just guessing at this point. so i get the intake off and start to pull the injectors out when i notice the valves were absolutely full of carbon buildup. im talking like a quarter-inch thick. it (pic in link below) took me hours to clean but i got it done and i also changed the spark plugs and the code went away. this is something i spent months and a thousand dollars on and it ended up being something simple. i would absolutely check the valves first and spark plugs. i don't know if you have a scanner where you can test each cylinder but 7 and 4 were not working for me, it was the spark plugs. Photos-001
pjdavep
Active member
Wow, those were filthy. The amount of sand and debris on the engine block is going to give me nightmares tonight
I definitely recommend the Infiniti induction service, where they hook an IV like drip into your air intake and let the gunk slowly melt away. I'm sure other shops do this too. After I cleaned my valves (rough clean), I had it done and the truck pushed out a ton of smoke for over five minutes.
Thanks for following up!!
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