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My A/F gauge is always changing under WOT. On nice, warm days I'll have first-second green bar at WOT. On colder days, or after driving a while, I'm only reading halfway in Stoich under WOT and the car will sometimes buck, obviously from not enough fuel. Well I have the B&M commandflo and I'll add another pound and still no difference. one thing I will add is that my sending unit leakes so if our fuel system is pressurized, could this be a possibility? And my EGR tube has a small hole in it. I already tried swapping VAF's and no difference, and installed a new O2 sensor and nothing. I'm at a total loss and can't think of anything else at the moment that it could be.

-Penny
 

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It could just be that you're expecting too much from an inaccurate narrowband sensor. Not to mention that its a one wire sensor which are even less accurate and reliable than those with more wires. Narrowband should not be used as a tuning tool and it bothers me you're paying that much attention to it.
 

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Tyler- LMFAO!!

Yeah, just like sick said, narrowband is good for measuring out WOT and closed basically. It's been said already on our car that a AF Gauge is pointless unless wideband is used.. Sick has one don't you?

ryan
 

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you can monitor your O2 sensor operation while your ECU is running in closed loop mode. other than that those guages are extra lightning.

you can use them in regular N/A cars, but in FI cars its usless.
 

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tyler886 said:
Tyler....You my friend, are the man! I don't even know what the problem is, but this matters not to me, because you ARE THE MAN!

Sorry, I hope you get the prob. fixed though.

lol, gg ty!

-brandoN^-
 

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Discussion Starter #11
91MazdaMx6GT said:
Tyler- LMFAO!!

Yeah, just like sick said, narrowband is good for measuring out WOT and closed basically.

ryan
I understand that I would need a wideband sensor to get accurate readings across the board. But what I'm talking about only concerns WOT. It isn't always constant when I drive. sometimes it will be in the first two bars of green and sometimes it will be halfway in Stoich. And I don't know what would cause that inconsistency to be there. I could care less what I'm running at during crusin' speed. Its just WOT that I want to know where I'm at.

-Penny
 

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"This unburnt fuel takes up valuable space in the cylinder but in forced induction applications cylinder temperatures can skyrocket and cause detonation. This extra fuel provides an anti-knock or cooling effect allowing for more power to be produced."

I thought that was a myth?
 

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Dyoel182 said:
"This unburnt fuel takes up valuable space in the cylinder but in forced induction applications cylinder temperatures can skyrocket and cause detonation. This extra fuel provides an anti-knock or cooling effect allowing for more power to be produced."

I thought that was a myth?
It's only going to burn what it needs. It "maintains" power and prevents overheating the cylinder but doesn't produce any more power.
 

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narrow is used by the ecu in closed loop mode only, you can see this at idle or under light throttle by the needle swaping sides every second or so. its pointless to watch it doing that though. in WOT the needle should be buried in the red (rich), if not you have a fuel(or ecu) issue somewhere...

fred.
 

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fredio54 said:
narrow is used by the ecu in closed loop mode only, you can see this at idle or under light throttle by the needle swaping sides every second or so. its pointless to watch it doing that though. in WOT the needle should be buried in the red (rich), if not you have a fuel(or ecu) issue somewhere...

fred.
Wrong. Autometer gauges and a majority of others as well, have their rich point being green.
 

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bemidjipenny said:
I understand that I would need a wideband sensor to get accurate readings across the board. But what I'm talking about only concerns WOT. It isn't always constant when I drive. sometimes it will be in the first two bars of green and sometimes it will be halfway in Stoich. And I don't know what would cause that inconsistency to be there. I could care less what I'm running at during crusin' speed. Its just WOT that I want to know where I'm at.

-Penny
I think you need a bit of education on the actual meaning of what you're seeing on your flashy little gauge there.

'Narrowband' O2 sensors detect A/F ratios on a VERY VERY limited range, say from 14:1 to 15:1. They are designed to 'watch' the A/F ratio as it oscillates from SLIGHTLY rich to SLIGHTYL lean...Nothing more. They are used ONLY at idle and at steady throttle cruise conditions.

Remember how I just said the 'narrowband' o2 sensor detects roughly between 14:1 and 15:1? Under WFO throttle (Kirk) your A/F ratio is going to dip as low as 10:1...WAAAAY below where a narrowband is going to do ANY good at all.

Thus that gauge is completely meaningless. Anything it's going to tell you at anything other than idle or cruise means absolutely nothing. Sorry :)

As for the buck...if it's a BUCk, as in pretty harsh you may be experienceing boost cut, or a boost leak. What boost pressure are you running? Check EVERYTHING forty times for leaks.

Laters
Ryan
 

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Omg you guys, rofl. Im pretty surprised this hasn't been closed yet. Anyway, go wideband if you want to really know what your a/f is. As for sick....let's all go over to his house and check our compression on his front lawn :p
 

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on another note...if you need to know the real time AFR on your car constantly, either you've got so many modifications and racing all the time that you actually need one...or you just want a 'gauge' to be cool.....either way....only to get an AFR is when you mod your car and take it to the dyno to get a wideband, or better yet, get one before and realize in stock trim, the 1g GT get's an average of 9.5:1 AFR with a low of 7.5:1 and no where near runs lean.

on the bucking...i'm assuming your running some sort of mbc...do you have a boost gauge? you should, since you bought a useless narrowband....but anyways, you're more than likely hitting fuel cut. is it doing this in 3rd, 4th and/or 5th?
 

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to the rest of you :

hotass6gt : not sure if you were trying to say widebands are slow, but if you were, they arent all slow, i've read about using four, and reading the individual pulses real time...

if his narrow band is in the purple (lean) when hes flooring it, something is up, but i am not the man to tell you what it is.

fred.
 
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