car is a 91 lx, dpfi

car runs pretty good, still getting good mileage but has been acting up at random after car is warmed up both in town and on hwy it will randomly feel like someone just pulled the parking break while i was driving and it kind of does a bucking type of issue, it will continue to do this untill the engine light pops on with a code 1 02 sensor and at that point car runs pretty good, can flip the key on then off and light will go away and will run ok for a little but will do the same thing over

ive replaced the o2 and still getting the same issue, car does have a new distributor, i recently did a valve adjustment and plugs are ok

kinda strange it pops o2 but replacing it didnt do anything, so something else must be involved to trigger it but i cannot figure it out

ideas?

 

Check your wiring (with a multimeter as well as a visual inspection).

 

It could be possible that too reach mixture or too lean mixture could be triggering the O2 sensor. Another possible reason could be wiring connections. Also check that the air filter is not dirty. From what you have mentioned, sensor is not an issue. Hope you have done valve adjustments properly.

 

air filter is nearly brand new, valve adjust was done just like 2 weeks ago( it did it before valve adjust to)

i dont see why i would be wiring though as in that case i think it would do it all the time, its gotta be something with lean/rich condition.
probably slap a new set of spark plugs in, then next time it does it i guess i could pull a plug and try to read it

 

I think you give wiring more credit than it's worth. Regardless, if you actually took the time to troubleshoot something then you could see if it was reading rich or lean. If it was lean throwing a few plugs at it wouldn't change anything.

 

i understand plugs wont change anything but it would be easier to read them with a fresh set, ive never had a wiring just randomly do something like this, especially when it seems to be something only happens when its at full operating temp, the second the light triggers for o2 it runs great, thats telling me its going to a alternate preset map and probably out of open loop

i have looked at the plugs but not exactally when it does the issue, they have a normal burn to them. In my 12-13 years of working on hondas i have never seen a issue like this


but for the sake of arguement, what wiring do you suggest checking with a multi meter? ive visually gone over everything already just making sure stuff is plugged in snug and no broken wires that ive been able to see

 

Since these vehicles have one wire O2's they aren't monitored until its up to temperature. There could be a break in the wiring or the insulation is broke. Countless problems really... Just because the code is random or only happens at certain times doesn't mean it's not the wiring. As I stated - you can see with a multi-meter is its running rich, lean, or neither. This way you will have a direction to move in. If there is an extreme reading of let's say 0.0v one would lean towards faulty wiring. Regardless, do as you please I guess since you want to argue suggestions.

 

i wouldnt of posted if i wasnt open to suggestions, not sure if you saw the end of my last post but im not gonna throw ideas out, just didnt think wiring would of been it but doesnt mean i wont check it

ive never multi metered a 1 wire o2 so, if you would be so kind to to explain what exact you mean.

 

I was throwing an o2 and I didn't have a multimeter either but I still just visually found an open in the wire, soldered it up and no more code. I had bought a new o2 and it was just that, so it can't hurt to look.

 

where did you find a open at? i just took my meter and checked continuity between shock plug and where it plugs to the o2 and that was good, also checked it against ground to make sure it wasnt grounding out

I guess im not exact sure what i should be doing with the multi meter to check the wiring, thats never been my strong suit

did throw a new set of plugs in to try and see how they would read when it started the issue but it didint do the normal bucking but the CEL did flip for o2 again in city driving, pulled the plugs and they do look a little lean, maybe one of my injectors is crapping out or something, it seems to be driving pretty good gets around 35mpg, idles ok

here are old plugs and one of new plug after light had came on

 

This should help you out...

http://m.wikihow.com/Check-Honda-Oxygen-Sensors

 

thanks for the link, you have a good tip for checking the wiring to the ecu itself?

 

well after doing that test i may have a bad o2 still

there was no rapid changes in voltage. but let me post how i did it make sure i did it right

unplugged o2 at the , hooked red wire to it and black to ground. started car and let it warm up

if i reved the motor and held it the voltage would goto 0.75 ish, if i let off and just let it idle it would slowly go back to 0.25-0.27 ish and pretty much stay there, i could rev motor again and it would climb back up to the 0.60-0.75 range