Is my air fuel ratio right??
 

I just finished installing the autometer air fuel ratio meter and it goes to one light before max in the rich area, can this be right? If so is there a way to lean this out without buying something like the apexi fuel controler, just while i save up to buy it... also whenever i change my spark plugs like once a year they are definatley burnt, mabey i am running rich? oh this is a na 91 rx-7 with a stock automatic computer, i neglected to change the computer when i converted it to stick shift,, thanks to anyone who can help...

Hey Eshaft. I can't help with the air fuel meter but maybe you can help me. I'd like to know what the number is on your ECU. Like my na has a N326, the Turbo has a N332. On the top of yours should be something of that order. If you get a chance please let me know. I'm making a list of ECU.

I just installed the same gauge two days ago. When the car is cold, it says my car is running rich (last light is lit). As the car warms up it starts leaning out. At idle the second light for rich lights up, so i guess im running rich. I would also like to know if theres a way to lean things out without buying the AFC (until i get the money for one). Hope this kind of helped :p

You might need to change your spark plugs and wires, if you have two red lights, lit up at idle. It could be that you need to clean your k&n filter. Only during wide open throttle, it should go to one green light. Hope this helps.


91 na
bonez fliter,exhaust, S-AFC
autometer a/f gauge :p

hey man i'm not sure if ur car has it but mine does. look right behind ur airbox. there should be a little thing that looks like an upside down t with a hole in the top filled w/ hard glue stuff. i'm not sure what its called but if u use an ice pick or something to scrape the glue out there is a screw under it. if u turn that screw u can adjust it from rich to lean or lean to rich. lemme know if u have one.

i was always told that those sensors are not very accurate let alone when they are cold.

True. Especially the Bosch ones thats are 1 wire. They rely on the exhaust fumes to warm up, unlike other sensors that heat up by themselves. The autometer gauge manual says that 02 sensors arent that accurate when theyre cold.
So does anyone know how to adjust the air/fuel ratio without using a SAFC (dont have money to buy one yet).

try the thing behind the airbox it works.

isnt that thing there to adjust the a/f ratio at idle only?

i don't think so. i turned mine all the way rich and drove and it ate mad gas. i turned the other way and i got some nice gas mileage. now (well b4 i got rearended that is) i turned it a little over midway towards rich and i took cars in races that i couldn't take b4

what are you guys talking about adjusting.. im trying to picture this, i suspect my car is running a bit on the rich side.. help a brother out.!!!

scott

its hard to describe. right behing ur air box there is a black thing that looks kinda like an upside down T with a hole in it filled w/ hard glue. scrape that shit out and turn the screw under the shit while ur car is at idle u'll hear a diff.

i was just looking in my manual and they describe this as an air bypass adjust screw... and next to it it says it is preset from the factory and should NEVER be messed with... so is this how you adjust rich/lean on a NA car w/o an afc?

scott

i had the same prob. w/ mine and i posted about it on here along time ago and thats what other peeps told me. i tried it and it worked for me. i don't have an air fuel gauge i just kept guessin until i felt i was gettin the hp and mileage i wanted
besides do u really trust anything factory? nahhhhh

yeah thats the Idle Adjust Screw. it has lean or rich on it. its supposed to be for idle only but if something gay were to happen with it i suppose.
Jason

to anyone who answered my post thanks i realy appreciate all the help .... I treied that turning the screw thing and i could hear the differance in the engine but saw no gague differance, as soon as i touch the gass weather it is to karuse or to floor it it jumps from red to green the second to last green, what is the deal caan anyone offer some advise thanks again

dosen't anyone know how to fix this help me please

Damn Ill have to try that since it looks as if ill be putting another rear end in my car. This time Ill rebuild it before just stuffing it in (but hey I was in a rush :)) I was running a 10.0 in the 1/8th with the 4.10 rear end. While the 3.90 rear end is nice for MPG it makes the car a dog on the road.

Think I can break into the 9's with this adjustment and a new set of 4.10's??

heres what my guage does
 

hope this will help,

until it warms up, usually a few miles down the road, it read last green bar rich. After warm-up, it goes to last two yellor bars to first two green bars. It doesn't matter what boost or accel rate, it stays pretty much within that range. Only when i decell. does it go lean. of the guage.

Hailers--checked the parts manual and the ecus appear to be the same no for manual and automatic.
Other comments: the mixture adjustment is for idle ONLY(unless somebody has messed with the ecu).
the description by snoopster is the way it should work,because on deceleration fuel is cut,depending on rpm,to one or both rotors.
in my experience running rich does not result in burned plugs,rather they get carbon deposits ie they look black.
assuming that the AFM hasn't been messed with and your air filter is OK look for problems in the fuel system,pressure control,dirty or stuck injectors etc.

My gauge on my TII reads one under full rich when accelerating, bounces between rich and lean at cruise, and goes completely blank with my foot off the pedal. It only registers when the throttle is depressed. Is this normal?

ok let's see if i got this right the screw on the air intake between the filter and the tube with the cap over it is only for idle air flow adjustment so it is overrided once you touch the gass...

second i think that we are all seeing the same thing the moment you touch the gass it jumps to rich one or two lights before rich..
now dosen't it seem like something is wrong there...

does anyone have one of these fuel controlers ,does it get you into the yellow range stoich or whatever they call it, if it does then was there a big differance in the way it feels and were you running rich before you put it in...

oh and now that i messed with that screw and it did nothing mabey it wasn't warmed up enough what is the factory setting how many turns from closed is it i want to put it back ...

Bump! I just want an answer to my question at the bottom. I'll write my own post if necessary, but I just am hoping someone can ease my concerns.

About the rich reading at idle....... Do you still have a functional air control valve? And air pump? A month or so ago there was a post that dealt with a phenomenem like your experencing. I use a digital meter to read the oxygen sensor off the ECU. When I first started doing this I noticed that at idle it was reading near 70 millivolts steady, no jumping, but when driving it was acting what I'd consider normal jumping on both sides of 40 milivolts. Then I put the air control valve back on and just happen to notice that at idle now, the volt reading was real low. About the same time there was a post on this site that mentioned the rich at idle. He had the same situation and the rich/lean screw did not help. What happens I think is with the acv operational your are mixing fresh air from the airpump thru the acv which sends it thru the internal engine passage (port air I think they call it, not sure) and the fresh air exits thru the rear exaust port (right where the oxygen sensor on Racing Beat Dual headers is) which gives the sensor a leaner reading than if the acv was disconnected or blocked off. I'll try to find the original post. That will take time.

SORTINO.....I consider that normal. I'm just using a digital meter, but when I go full throttle I get a rich 70-80 millivolts steady reading. At cruise I get a meter that jumps on either side of stoic. If its just idling I get a steady minus something unless I have the acv blocked off and then I get 70 maybe 80millivolts. Same thing you stated, just do not have a air fuel meter.