another fuel trim question...

[gimmie11s]

hey guys..

im trying to adjust the fuel trims on my 92 gsx but nothing seems to make them change. the low is 139, mid 119, and high 139. this suggests im pretty lean. how long must i wait for the ecu to respond to afc changes? it seems like nothing i try changes the trims. do i need to reset the ecu? thanks..

mods are:
fp green
550s
110 leaded
1g super hacked maf (lower section removed, no flaper door)
pocket logger

-d

 

[1LE]

what are you changing them with!?!?!?

 

[gimmie11s]

safc

 

[Bohrn]

you've gotta get that leaded gas outta there.

And your o2 sensor is probably shot by know so go get another one, and then try again.

 

[tan]

Originally posted by Bohrn
you've gotta get that leaded gas outta there.

And your o2 sensor is probably shot by know so go get another one, and then try again.

o2 sensor only works in close loop, meaning that it only works when your on idle for smog purposes and fuel conservation, etc other than that you can have a bad o2 and still have the same, more or less reading or nothing at all

 

[kpt4321]

Wrong.

O2 does only work in closed loop, but that is not just idle. Closed loop is any idle or cruise condition, which is also 90% of your time spent in the car. The O2 sensor is mainly to make sure you have the right A/F mixture so that the car runs right.

Fuel trims NEED a good O2 sensor to work properly.


....Kyle T.
93 TSi AWD "TURBO4"

 

[tan]

Originally posted by kpt4321
Wrong.

O2 does only work in closed loop, but that is not just idle. Closed loop is any idle or cruise condition, which is also 90% of your time spent in the car. The O2 sensor is mainly to make sure you have the right A/F mixture so that the car runs right.

Fuel trims NEED a good O2 sensor to work properly.


....Kyle T.
93 TSi AWD "TURBO4"

i probably read his post the wrong way then, change the o2 and take from there, in the mean time i thought he was talking about when his car is underload that his fuel trims are lean...which the o2 is not NEEDED to be change, but to find if there are any leak in the system first then if you have the dough then change the o2 or if you have a friend with the same car ask to change the o2 to see if it changes the value
thats just my opinion