Topic: high 02 readings fail me in smog in cali??

[Makohon]

like the title says..... i am pretty sure i know why it failed or what led to it failing... when i first built the truck i ripped out 1 or 2 wires from the front senser and didnt find out till about 2,000 miles later.. soo that means my truck had been running rich correct?  and led to the front senser getting f'd up and also my rear sensor? for the rear sensor it was plugged in for lets say the first 2k miles when the front one was disconnected.. then i put a magnaflow muffler and ran bigger pipe so i left the rear o2 senser off at the 2 k mark and then fixed the front o2 senser at the 2 k mark... now at 4 k i try and smog it and it doesnt pass the o2 test... do you think this is very possible that is why i failed and that i probably screwed up both sensers? do you think i may have also done damage to my engine ect?? the front senser has a brownish looking color and a little bit of whitish grey color to it and the rear senser is a greyish color? no i didnt use any silicone anywere nor is my head gasket leaking... and how much should i expect to pay to get the sensers tested?

[twistedtoy92]

well.............. i'd just get new sensors because it is more than likely that they are original and as long as they arent too horribally expensive..... you'd be better off droppin some new ones in!!!!!!!

[brainlessfool]

gen. a high O2 reading means a exh leak.

[jimbo74]

new o2 sensors are usually only $30

[subbrat]

High o2 can be from a missfire

[brainlessfool]

High o2 can be from a missfire

Think that will give you a high HC reading

[Makohon [OP]]

damn my bad people..... it says       CO%
                                                         MAX       GP         MEAS
                                            15MPH    0.76       2.26       2.89
                                            25MPH    0.65       2.15       2.70
                                 

 also he highlited this but he didnt say i failed it??


                                                  HC (PPM)
                                                              MAX          GP          MEAS
                                               15MPH      121           296           177
                                               25MPH      96             246           164

[jimbo74]

looks like it failed... its not yet a gross polluter which means it isnt that bad, but still bad enough to fail.... gross polluters get to go to refs if its bad enough

[Makohon [OP]]

it did fail as a gross polluter....... what exactly does it mean when its a gross polluter? i mean.... say it is my o2 sensers and i change them out... can i bring it back to a smog station and get it smogged or do i have to do some other $hit?? and what is the HC (PMM) reading??

[Makohon [OP]]

ok so i was lookin at my fsm and it shows no rear senser? but i have one... it doesnt mention anywere i saw about a second senser?

[fordh8r]

High o2 can be from a missfire

yes high O2 readings can definitely come from a misfire.

gen. a high O2 reading means a exh leak.

very unlikely since an exhaust leak would allow oxygen into the exhaust system which will cause much lower readings (lean)

looks like it failed... its not yet a gross polluter which means it isnt that bad, but still bad enough to fail.... gross polluters get to go to refs if its bad enough

gross polluter does not mean that it failed miserably it just means it failed. It's kinda like calling someone who is 5 pounds over weight obese.

damn my bad people..... it says       CO%
                                                         MAX       GP         MEAS
                                            15MPH    0.76       2.26       2.89
                                            25MPH    0.65       2.15       2.70
                                 

 also he highlited this but he didnt say i failed it??


                                                  HC (PPM)
                                                              MAX          GP          MEAS
                                               15MPH      121           296           177
                                               25MPH      96             246           164

By these numbers I would say if you haven't tuned it up in a while, do so. If you had a misfire condition or a rich condition because of the wire problem with your O2 sensor it may have caused damage to your Catalytic converter and it may need to be replaced. Also if you haven't changed your oil before smogging it that could easily contribute to a certain failure for smog. Two very important things to consider before smogging your vehicle Tune-up and oil change. They can make a world of difference. Since you didn't mention the tech failing you for anything else I'll assume your timing and EGR components are functioning properly. As far as the 'meas' numbers go anything above 'max' is failing. It has to fail a certain number of times before they will send you to a referee station where they will make a decision about you smog status.You might find some info on the web site for Bureau of automotive repair (sorry I don't have a link).

[brainlessfool]

A high O2  IS a high oxy reading. and that means a exh leak. O2=oxy.
butt what we have here is a high co2 reading with a high HC reading too. most liky it is running rich.

HC is unburned gas

CO is a product of combuston.

so to much gas going in= to much unburned gas coming out.ie HC.
you o2 senser is the frist place to start alone with a gen. tune up if it's running "funny"
used to be that if you got a G.P. you had to go to the ref. to get it smogged, and had to go evey year from then on too. think that's been changed, butt it been a while sense I let my smog lic. go.

[Makohon [OP]]

hmmmm... the running rich thing... my exhaust smells a bit like... hmmm i guess kinda smelly... like i guess it would if it were running rich... also when i did my oil it smelt kinda like a lawnmower.. i dont recal ever smelling this smell in my oil before.... also should i worry about harming anything if its running rich cuz an o2 senser? well besides harming o2 sensers and my cat? in otherwords should i not drive it? it runs fine.... just changed the oil.... timing is set 5 degrese..... one thing i havent done was check the valves....

[fordh8r]

A high O2  IS a high oxy reading. and that means a exh leak. O2=oxy.
HC is unburned gas
CO is a product of combuston.

All true!  While a high O2 content indicates high oxygen it will show as a lower reading in volts from the O2 sensor (lean) and will show higher voltage readings during rich conditions. For example, as with an OBD II system the O2 sensors downstream of the Cat will read about 0.0-0.1 volts DC (with a properly functioning Cat) which is normal since the Cat will convert spent gases to mostly Oxygen and CO2 and the front O2 sensors will determine fuel ratio changes. High readings will be from 0.5 to 1.0 volts DC (rich), low voltage readings will be from 0.0-0.4 volts DC (lean). 

[fatt_matt]

hmmmm... the running rich thing... my exhaust smells a bit like... hmmm i guess kinda smelly... like i guess it would if it were running rich... also when i did my oil it smelt kinda like a lawnmower.. i dont recal ever smelling this smell in my oil before.... also should i worry about harming anything if its running rich cuz an o2 senser? well besides harming o2 sensers and my cat? in otherwords should i not drive it? it runs fine.... just changed the oil.... timing is set 5 degrese..... one thing i havent done was check the valves....

im running yj right now... and its not smogged becasue my EGR vaulve isn't clean.. that might be your problem to..
im guessing... the thing abotu smog is its difficult to guess what's wrong because it can be many things.. as we can see from this thread... but i think ford hater has teh strongest point...