I was thinking about this because i was having problems with part throttle tuning. if we put a resistor inline and lower the output signal to the ECU from the 02 sensor, the ECU will think it is running leaner and richen things out taking care of part throttle lean fueling issues.
Has anyone tried this? i think if we put a very small value resistor inline it would work.

Any comments?

Thanks
James

/raises his hand

I only did the one after the cat. I did it according to a sheet I found on a neon website. And yes IT DID WORK, still does. I still can't beat the front o2 sensor thou.

ya danny, did you do it just to get rid of the CEL? i was thinking of doing it on a duning basis, maybe a POT that i can adjuct from inside.
lates
james

I think another solution already implemented by the J&S safeguard devices, is to switch the TPS to WOT or 5v when under boost. This will in turn make the fuel trims go to open loop and also certainly solve any partial throttle fueling issues.

It's still very much on my shopping list. :-)

i built a little circuit last night that incorporated a small adjustable potentiometer and tested it electrically. i can lower my 02 sensor output by .01-1.5 volts. This theoretically will make my ecu think the car is running leaner than it really is and increase the fuel delivery proportionally. I will install it in my car either tonight (if it freaking stops raining) or sometime next week and try it out. if it does work out well, that means that we will have a real means for richening up part throttle areas. and if say the temperature gets hotter you can trim it with this little unit by making the car thing it is leaner yet. hell if it works out i may even make a few of these to sell to some nice people.

lates
james

Thats definately a clever idea. I'm very interested to hear how that works out. Good thinking James :thumbsup .

James I'd be definately intrested in that man. =) So far no check engine light, but I know it's comming.

- 98 5SPD GST (crankwalked and blown turbo)
NEED BIGGER TURBO!!}(

I'd certainly be interested to hear if it actually worked. I've wanted some control over the O2 sensor for part throttle boosting. I discounted the resistor idea because I was under the impression that the ECU looked for frequency (not just amplitude) of the O2 signal to determine fuel flow. You're the first person to try this (that I know of), so I hope it works as a long-term solution. If it works for you, I'll certainly try it out.

Corbin

'95 ESI-T
HRC+FMIC+ETC...



Gimme fuel...Gimme fire...Gimme that which I desire

i was also wondering if it would be possible to hook up an AFC to the 02 sensor and modify its output, now that would be cool.

lates
james

okay, i am planning on trying to put an afc instead of a resistor inline to modify 02 sensor output. i need to know some information about the afc if anyone knows. the settings for pressure, like the in 7 out 7 dealio, what exactly does it do, does it change the amount of input and output? i would think that if i was inputting say 2 volts and i had 0 correction i should be outputting 2 volts. i need to know exactly what these settings do in order to determine if i can do this. i decided to go this route, because i can control the changes a little better if at all possible. we'll see. please help.

Thanks
james