Is it me or has anyone else noticed alot of the symptoms of a rich running car with their 07 ? I notice the car studdering a bit at idle as if it is warm and a bit on decel.

 

No

 

If anything mine is running too lean until it gets near redline...

 

Sound's like I'am being a bit paranoid. I should pull the plugs out to see what they look like.

 

My car is running very lean up til 5k rpms

 

Yeah, if anything it runs a little lean...

 

To comply with emissions at any time other than serious acceleration above 3,000 rpm the engine MUST run spot on at 14.7 AF for cats to function.

Any AF outside of 13.8-15.5 the cats are useless in converting HC and Nox.

 

When I had my car on the dyno a couple weeks back the tuner said I was running a tad rich and could use a mild tune even being stock on my '07.

 

What do you make of this chart Q45tech?

 

At WOT all bets are off since emission are never considered under these conditions.

Nissan uses richer than 12.5AF TOO COOL the combustion to reduce knock under poor US quality gasoline...............also to be future protective if as injectors age they become varnished and reduce flow becoming leaner.

Luckily running richer than norm doesn't decrease power nearly a fast as running leaner than norm.............some engines actually run as rich as 10:1 AF with minimal reductions............the excess just blows out the tailpipe.

Also cats are protected by running rich which lowers the operating temperature.

 

aIR VOLUME LEARNING PROCEDURE ANYONE?

 

Yeah but if you go to rich you could melt the cats.

 

I notice every time I clean my tail pipes there is black carbon residue on bottom side of the tips. My guess is it is running a little rich.

 

I just installed Berk Tech. test pipes and Fujita intakes and when I go WOT in 1st it studders a little till about 3K then it's on it. Too much fuel? I don't remember it doing it with the intakes alone so I wonder if the test pipes are causing it. Thanks for the info.

 

The manufacter tuned it to run a little rich to protect the motor.

 

WRONG WRONG WRONG. IT'S TUNE OT RUN LEAN AT IDLE. THE OLNY TIME IT SHOULD RUN "RICH" IS AT START UP AND FOT. IT SHOULD FLIP FLOP FROM LEAN TO RICH. I WORK ON THEM EVERY DAY. I'M A NISSAN TECH IN MARYLAND.

 

tuning properly will make it run better and give you max power.

you always want to run a little rich (about 13.X AFR) to make best torque.


the car should never run lean. it should run at stoichiometric AFR which is around 14.7 most of the time, when you REALLY step on it it typically goes a little rich.

changing mods / parts can modify your AFR curve.

 

Adding test pipes and a Fujita intakes can't change the amount of fuel being delivered to the engine, so I doubt your engine is getting to much fuel. Your Fujita intake will increase air flow and could lean out the A/F ratio. Make sure both your test pipes and Fujita intakes are installed correctly and nothing was left unplugged or disconnected.

 

my z runs lean as well in upper rpms. a bit scary at times.