stylett9

iTrader: (9)

LOL!!!!!!!!!!!!! I can't even count how many times I've been told that one.. so irritating.

dirtbikr

I never get told this because I have an auto. the dealer just shook their head and said "i dunno"...

stylett9

iTrader: (9)

you have an auto and your sputtering? Did you watch the videos a few pages back to verify we are talking about the same sputtering? If so, your the first auto i know to have this isse :-(

thehoodz

There have been a couple auto's who have had this problem from what I read, maybe three. If so, count me in as 4. It SEEMS a little harder for us to tell since a lot of us in full M mode don't watch our RPM's but this is with out a doubt my issue. I noticed for the first time today that the needle does bounce roughly around 1200-1800 rpms.

From reading all of this I think it may have to do with the air flow. I'm starting to think maybe our cars are running a little lean and it is the ECU trying to fix this(not saying it's an ECU problem but maybe an air flow problem and our ecu doesn't know how to fix it).

Has anyone had a dealer check if there's too much air?

Also, has anyone checked the fuel injectors? Maybe the mixture is off. If so that could cause this I believe and would also explain the change in tone from exhaust.

IvoryPearl07g

OK....lots of information below and some first hand experiences...grab a coffee and enjoy my published novel below.


I want to follow this thread since i've read about a dealer replacing everything on another stock car under warranty. At last count, they are $3000 in replacing parts/sensors so far with no fix. So, i am going to continue to work on solving it myself. I really want to fix it, but if i know absolutely no dealer has put a TSB out on the issue, i might have to put it to stock and sell the car. Anyways...long post so bear with me.


i have been dealing with the same issues myself over the past year. it all started with the occasional flat/blurbly sounding exhaust note, a substantial loss in power, and some bumpy acceleration at times. It eventually developed into a horrible jerking on acceleration and would go into limp mode. The code at that time was P1084....Exhaust Valve Timing Control****(side story at bottom). sooo......

.....I thought i narrowed it down to the exhaust cam sensors. Cause it was obviously an issue(to me atleast) with the exhaust cams being way off timing. this problem was intermittent. SO, I got new connector plugs for the exhaust cam sensors from a nissan dealer and replaced them all because i seemed to replicate the sound by messing with the connections. The problem seemed to clear up for a month or so.

But over time it came back gradually and i got a new code. PO420 catalyst efficiency. SO i bought GTM resonated Test pipes which guarantee no CEL. The problem is still there and it can go from a sloppy slow & loud POS to the most sexy sounding blazing fast V6 ever. I want to figure this out!!! My code now is P2A03....A/F sensor 1. sooooo.....

.....I thought that it was an exhaust leak. I have read that the newer OBD2 cars absolutely cannot run good with out the o2 sensors getting the most accurate information. So i replaced the gaskets on both ends of the test pipes because they were pretty beat. the car did drive good for 350miles and it again threw the 0420 catalyst code and lost power while sounding like crap a couple of times.

part numbers for catalytic converter exhaust gaskets-
20691-Z33002 for the upper flange
20692-Z33001 for the lower flange

So now i am moving on to my next series of theories.

I was thinking there is either a small leak somewhere on the intake side or on the headers....OR....there is one or more leaky/clogged injectors which is messing with the cars a/f mixture. So i just picked up some fuel system cleaner that i have read positive independent studies on and got some CRC Mass air flow cleaner. I added some of the fuel system cleaner, cleaned the MAFs, unplugged the exhaust valve solenoid plug/cleaned it, and checked for loose anything on the intake/plenum/vacuum. Its running pretty darn good for now, i will update if the problems occur again.

---------------------------------------------------------------...
BUT, the pessimistic part of me wants to continue looking into the exhaust camshafts.....because of the story below...it just seems that if there is such a force in the full advance/retard movements of the camshaft, that it can snap the dowel pin on the cam gears, there has to be an erratic electronic signal being sent to the ecu that causes said advancing/retarding actions on it.

And to my ear through my exhaust during the issue, i hear full retarded exhaust cam timing(sometimes kind of fluctuating from full retard to half retard) and a really rich condition on one side of the motor.



anyways.....................






***Side story about the first P1084 code i had....
Same issue was going on with another 07 G35 sedan vq35hr member on G35Driver.com. The dealer kept replacing the exhaust valve timing sensors. After several months of this, the car finally blew up. Apparently something failed on the exhaust camgear/shaft/solenoid. when the cam slapped over, it jumped timing and---- all the valves bent-pistons on that side had holes- the other side jumped timing-those valves bent-and those pistons cracked.

It was an absolute failure. The dealer wouldnt cover the warranty because they deemed the aftermarket air intake to of caused the problem. He had to either pay $5000 to get the car back in pieces....or $13000 to get it fixed and back to him. Needless to say he whipped the credit card out and had it fixed. So this possible outcome has been in the back of my mind.

Now hearing/typing that story, does it not sound like a low oil pressure situation that might be happening in these motors??????????? Timing chain tensioner is oil pressure driven and exhaust timing solenoid is oil pressure driven! I NEED INPUT! lol

Tac-M

iTrader: (17)

^ omg man... dont scare us this much. i had a little sputtering going on with my z as well... i still do. i do have the p420 and p430 all the time now, but it is because of my TP's . my car has every bolt-on as well as a custom ecu flash. the little hick-up happens in the middle of the warm-up cycle so i just know by now when it is about to start, and i just take it easy .

IvoryPearl07g

man it struck again today when i took it out to run across town. it was about 2 minutes into the drive and it started to spit and sputter and had maybe all of 100 hp. i had tried to restart it a couple of times like i usually do with no avail.

soooooo.... i had to pull over and clear the 0420 code then restart....it still had the blurbly sounding exhaust(sounds like the exhaust cam fully advancing and retarding over and over), but it cleared up after a minute of driving and ran like a scalded dog the rest of the trip there-n-back.


i tested my voltage on the battery(12.7v)and alternator(13.9v) output, they were fine. i am still thinking its an issue with a sensitive sensor picking up a very small abnormality that causes the ecu to try to resolve it with timing and fuel trim adjustments.....the question is, WTF is causing the abnormality!?

*****serious side question for any nissan obd2 gurus....everytime i clear the code and just drive on that first restart, it will flash the CEL at certain rpms and conditions. Is it the car telling me there is an abnormality at that point in time? becuase it happens around 4500 rpm, sometimes while idling, and anytime letting off the throttle. Almost sounds like a vacuum sensor or PCV valve............ this is such a HEADACHE!

Tac-M

iTrader: (17)

yes, if CEL is flashing something is happening . it should only light up on start-up... the only code i was able to reproduce wile sputtering was a misfire on one of the cylinders. i was in neutral, and just kept the rpm in that "sputtering range" for about a minute. again, that is the only code i have ever had because of this issue.

IvoryPearl07g

awesome, thanks for some input. If it is telling me something is happening, i am lead to believe it is either a cylinder misfire or an extremely lean condition when letting off the throttle(which in essence is a misfire upon predetonation).


but i am still not quite understanding why at the exact moment of the warm up cycle it looses power and spits/sputters so badly.

i know to warm these cars up so quick, the car runs lean and keeps the timing at a set point to avoid detonation. then it will ease the fuel back into the mix and put advanced variable timing back to normal. its almost like at the changeover point of going into normal operating temp mode something is amiss.

Thinking about it, im starting to wonder about the coolant temperature sensor. its a possibility that the sensor is sending erratic signals out. And that can cause the changeover moment to flip the timing/fuel back-n-forth at the sensitive changeover point.

*i forgot to mention i changed the exhaust cam sensors about 6 months ago with known working sensors to test them.....no affect to them in either way.*


***man wtf? I just went back a couple of pages to see that some people confirmed its the throttle components inside the throttle bodies. is that true? On my 2002 sentra specV i had, i went through 3 throttle bodies in 4 years thanks to the integrated Throttle position sensor. ***

zettahertz

hmm... damn. I'm having the same issue with mine now. Didn't know so many people have this problem. I thought it was an exhaust leak or something. It gets a weird throaty noise when it starts to hesitate and jerk. Then disappears when it gets warmed up. Most noticeable when in a parking lot.

edit: hmm, wonder if running 0w40 Mobil1 might be the cause. I remember it used to have the throaty noise but no jerkiness w/ the 5w30

BlaQ350z

iTrader: (1)

I have been having this problem for over a year now, i got my car shipped from Houston to Kuwait and it only started happening after i got to Kuwait (~15000 miles). Took it to the dealership 4 times but they could not figure it out. I never expected so many HR's with this annoying problem, so someone please make this thread a sticky.
I really hope a solution is found soon

bardabe

iTrader: (5)

i got used to it by now lol

MM'08_350Z

iTrader: (5)

As weird as it may sound I just got back from retuning my HR from UPRev and made 289.5whp and 243Tq. Anyways I had asked the guy if he had any idea of the sputtering while engine heating up he said he had heard about that on many HRs and he said he could probably fix it. I knead doubted it but waking up this morning I took my HR for a lil ride. And no sputtering what so ever, I am very happy. But my CEL came on I'm thinkng cuz of my test pipes.

bardabe

iTrader: (5)

same thing with me when i got mine tuned, it came back later. lol

MM'08_350Z

iTrader: (5)

I hope not. Now about the CEL I thought It would be my test pipes but then the guy said it's cuz of the dyno since it's been running on the dyno with only using the rear tires and the front tires stay put that may have caused a CEL. WhAT do you all think?

dirtbikr

I think you need to get the code read before we play your guessing game, free at autozone, painless procedure.

MM'08_350Z

iTrader: (5)

Thnx for your help ****bag.

bardabe

iTrader: (5)

it has to be something with the Cam Timing / Phasing after speaking with a couple vendors they all say it got worse when they installed cams, so thats a good hint right there.

stylett9

iTrader: (9)

people come and go on this issue... You'll eventually get tired of trying to figure it out like the rest of us. hahaha

IvoryPearl07g

well im still here on this issue and like clockworks its always around the 2min mark into the drive. then after 2 more minutes it goes away. if i drive it for 15-20 min straight it feels like its at its fastest and stays that way.

-so its narrowed down to the warmup proceedure. It does seem like the ecu aggressively adjust the motors TIMING/FUEL.

-there is a sensor somewhere on this motor/transmission that is related to the motors temperature.

-that sensor is sending a signal at the exact same temp that the ecu does not like and tries to fix through adjustments in timing and fuel trim.


does anyone have a hookup with a tuner or OBD specialist/tech that can watch the various workings of the car during the warmup problem????