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hey mate,

i am having this same problem, also using shit tons of fuel(roughly 200km to a tank). my car needs the o2 sensor replaced. i have ordered it from nissan and will let you know how it goes fixing it.

my car blows fuel smoke on full throttle. the idle likes to wander from 800 to 500. and when it goes to 500 it sounds like it's missing.

my stag was never good on fuel from the day i bought it. and only threw the o2 sensor code, 6 months after i bought it.

will keep you informed

Where are you djtee? There is something seriously wrong with your car for it to be going through that much fuel, I doubt the o2 sensor will be the only issue, as the rich running will have ruined it. Could be worth sticking the Consult 3 on it.

Where are you djtee? There is something seriously wrong with your car for it to be going through that much fuel, I doubt the o2 sensor will be the only issue, as the rich running will have ruined it. Could be worth sticking the Consult 3 on it.

im in sydney mate, i purchased one of your afm's about 3 months ago.

i've had it plugged into a diagnostic computer, and all it came up with was the o2 secsor, it wasn't giving any signal at all...

today i checked for airleaks/broken airlines to the fuel regulator, but it was all sealed nicely.

Hi guys,

well i ripped the cat out out the dump pipe and fuel economy has returned to normal, still have a bit of a rough idle but the power down has returned and driving great again, im not sure what i would have to do to correct the idle but i am happy that the car is back to normal driving if not better!

only thing i can think of is replacing the o2 sensor. might try that soon.

thanks heaps Scotty!

I hope this cant help other people, and i would recommend getting rid of that constrictive front dump/cat!

  • 2 years later...

I am having a similar issue, but it's only missing under load.  When it starts making boost, it seems that it starts to have a miss.

The interesting thing is I ended up getting a fault code a couple of times indicating a coil issue before this missing under load started, which I have cleared, reset, dropped the power from the battery and everything goes back to normal.  The coil issue would only happen after leaving the car for a while, starting and then it would run rough (like one cylinder was down), then all of a sudden come good, but the engine check light would come up.

  • 1 year later...

I'm still having this issue.  I've checked all the plugs, replaced all the coils (thinking it was a bad coil and I had done 150K on them...)

For some reason it's an intermittent fault.  It happens when the car is idling (cold), feels like it's missing, but it's not regular.  Then under full throttle (so boost) it will miss regularly.  No fault codes, no engine light.

 

Does anyone have any thoughts?

I've had a bit of trouble with old and hardened manifold vac/boost hoses blowing off under boost. Last one was difficult to spot since the fuel rail (fuel pressure regulator) end had come off. I now know what to look for when the idle goes a bit wonky... but it shouldnt happen now that the bad hoses have been replaced.

You could start the motor and remove the non-manifold end of each hose one at a time. Block the end with your thumb to verify there's vacuum and that the idle changes. If you have a vacuum gauge check what the manifold has at idle.

 

Heya Stabby man.  Yes, your thought process is along mine aswell. I thought it was a vacuum leak somewhere initially, and found a hose that I thought was causing the problem that was going to the OEM ECU boost sensor, but after replacing said tube, the issue is still there.

Now working with my local trusted mechanic, I have had plugs replaced , the issue still exists.  I am currently using 'Hanshin' coils from Ebay (supposedly the same as OEM...) and currently suspect these may be causing the issue.

Does anyone have a cheap way of buying OEM Nissan coils.  Currently Kudos Motorsport have them for $136.40 (NIS-22448-AL61C)

The frustrating thing with this is it's intermittent. The car will idle fine, but then all of a sudden miss and stumble.  The only reliable thing is when it's under load it will miss.  Thinking this is coils currently.

Mine would idle ok when cold, and when hot it would idle for a short time ok, then get rough. With RB motors i've heard of circumstances where the coilpacks get marginal when they're hot. Havent heard of that with VQ coils but it could be a thing.

Oh - the other issue i noticed when there was a vac leak was that both fuel trims would max out (one at +25% and the other at +10%). info  https://www.sau.com.au/forums/topic/280322-m35-obd2-or-is-it/page/4/#comments

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