will a bum 02 cause a missfire under load?
- Thread starter daturbosix
- Start date
what code? unless its constantly reading low/high or is skewed it shouldnt
unplug and leave disconnected and reset fuel trims and that will run you on base fueling so you can eliminate that possibility.
prob ign cables though since ya had the intake off you prob broke one internally it will slowly get worse as the break in the wire burns the gap open farther and farther
unplug and leave disconnected and reset fuel trims and that will run you on base fueling so you can eliminate that possibility.
prob ign cables though since ya had the intake off you prob broke one internally it will slowly get worse as the break in the wire burns the gap open farther and farther
the code was P2195:
Oxygen (A/F) Sensor Signal Stuck Lean
(Bank 1 Sensor 1)
i did notice that when i reinstalled the COPs they did no "snap" on. like they didnt pop like pushing a normal plug wire onto a plug. i have NO idea how these modulars are. this is the first ive toyed with.
i went around the engine while it was idling and pushed and twisted each COP. i then went around and unplugged and reconnected. no noticable change. however the moment its under that certain amount of load.......
Oxygen (A/F) Sensor Signal Stuck Lean
(Bank 1 Sensor 1)
i did notice that when i reinstalled the COPs they did no "snap" on. like they didnt pop like pushing a normal plug wire onto a plug. i have NO idea how these modulars are. this is the first ive toyed with.
i went around the engine while it was idling and pushed and twisted each COP. i then went around and unplugged and reconnected. no noticable change. however the moment its under that certain amount of load.......
no it will cause a lean condition...the o2 sens only senses oxygen concentration compared to atmospheric oxygen concentration.
a missfire will dump unburned fuel AND oxygen into the exhaust..the o2 will read lean, the pcm will compensate by adding fuel...when this doesnt correct it it will trigger a lean bank code if the missfire monitors dont detect the issue
iirc ford cop doesnt have "clips" its just a steel spring inside the boots that touches the coil terminal and theplug end.
i was thinking the old style 4.6 with wires...sorry
rears are diagnostic for catalyst monitors...foulers work great for cat delete's with older style cat monitors...newer systems use multiple tests to test cat oxygen storage capacity so the foulers/sims dont always work for them (fuckin fed emissions)
that may or may not reset the fuel trims but resetting trims will only make it trip a lean code faster...swapping the two without zeroing trims will mean it'll take a little longer as it is in a "learned" trim mode and not as agressivly retesting trims.
from my im240 diagnostic days i can tell ya this...ford has an engine managment philosophy of keeping the cel light off unless its required by fed emissions standards...so if it tripped a code...that triggered the light...you def have a fault...its when them bastards wouldnt trigger anything that i had fun diagnosing em
that may or may not reset the fuel trims but resetting trims will only make it trip a lean code faster...swapping the two without zeroing trims will mean it'll take a little longer as it is in a "learned" trim mode and not as agressivly retesting trims.
from my im240 diagnostic days i can tell ya this...ford has an engine managment philosophy of keeping the cel light off unless its required by fed emissions standards...so if it tripped a code...that triggered the light...you def have a fault...its when them bastards wouldnt trigger anything that i had fun diagnosing em
if you dont have a scantool that will reset trims, then yeah bat disconnect is the way to go...usually 5-10minutes is enough for all power system caps to discharge, crossing cables while disconnected will drain the caps even faster so yeah you could do that and be extra sure it did a hard reset.
you can unplug o2's before or after..wont mater...you trigger B1S1 and B2S1 heater/fault codes so the light will be on right away as soon as you start it but your looking to see if fueling is skewed by the o2 enough to cause the missfire or whether the missfire is causing the lean fault.
my guess is youll still have the mis as im pretty sure your lean 02 fault is the effect not the cause
regardless its a cheep and simple test and i have seen o2's that get contaminated on their atmosperic side/sensing side, bad enough that it will massivly skew its "stoic" switchover point at 450mv
its not often but i have seen it so it's best to rule it out since its relatively easy.
afterward you can clear trims again and plug em back in...if the lean stays on bank 1 and doesnt follow the sensor start diagnosing ign stuff on bank1
was there oil in any of the COP bores/bottom of the boots?
when its missing is the cel flashing?
btw id suggest investing in a snap-on brick/etc so ya'll can check the missfire monitor counts....makes that shit real easy...if ya get one with the programable cartriges your good to 04 and can read generic obd2 for 05+
i dont know what id do without mine
you can unplug o2's before or after..wont mater...you trigger B1S1 and B2S1 heater/fault codes so the light will be on right away as soon as you start it but your looking to see if fueling is skewed by the o2 enough to cause the missfire or whether the missfire is causing the lean fault.
my guess is youll still have the mis as im pretty sure your lean 02 fault is the effect not the cause
regardless its a cheep and simple test and i have seen o2's that get contaminated on their atmosperic side/sensing side, bad enough that it will massivly skew its "stoic" switchover point at 450mv
its not often but i have seen it so it's best to rule it out since its relatively easy.
afterward you can clear trims again and plug em back in...if the lean stays on bank 1 and doesnt follow the sensor start diagnosing ign stuff on bank1
was there oil in any of the COP bores/bottom of the boots?
when its missing is the cel flashing?
btw id suggest investing in a snap-on brick/etc so ya'll can check the missfire monitor counts....makes that shit real easy...if ya get one with the programable cartriges your good to 04 and can read generic obd2 for 05+
i dont know what id do without mine
if you dont have a scantool that will reset trims, then yeah bat disconnect is the way to go...usually 5-10minutes is enough for all power system caps to discharge, crossing cables while disconnected will drain the caps even faster so yeah you could do that and be extra sure it did a hard reset.
you can unplug o2's before or after..wont mater...you trigger B1S1 and B2S1 heater/fault codes so the light will be on right away as soon as you start it but your looking to see if fueling is skewed by the o2 enough to cause the missfire or whether the missfire is causing the lean fault.
my guess is youll still have the mis as im pretty sure your lean 02 fault is the effect not the cause
regardless its a cheep and simple test and i have seen o2's that get contaminated on their atmosperic side/sensing side, bad enough that it will massivly skew its "stoic" switchover point at 450mv
its not often but i have seen it so it's best to rule it out since its relatively easy.
afterward you can clear trims again and plug em back in...if the lean stays on bank 1 and doesnt follow the sensor start diagnosing ign stuff on bank1
was there oil in any of the COP bores/bottom of the boots?
when its missing is the cel flashing?
btw id suggest investing in a snap-on brick/etc so ya'll can check the missfire monitor counts....makes that shit real easy...if ya get one with the programable cartriges your good to 04 and can read generic obd2 for 05+
i dont know what id do without mine
nah, the spark plug bores were clean as hell. the only thing might have been a little anti freeze leaked down those holes, but im sure its dry by now. i did the intake this past saturday.
the CEL is on solid all the time. never flashed.
what are the odds its a junk set of plugs?
so i went and saw jeff at advance.. we scanned it. that bank 1 primary sensor which is not in bank 2, is reading .000 accross the board. i went ahead and picked one up. stuck it in, and now draining the system to reset everything.
we'll see what happens.
i was throwing a total of 7 codes when we scanned it agian about 45 min ago. egr codes, map code, b1s1 efficincy code just to name a few.
the rear o2s are reading as normal.
we'll see what happens.
i was throwing a total of 7 codes when we scanned it agian about 45 min ago. egr codes, map code, b1s1 efficincy code just to name a few.
the rear o2s are reading as normal.
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