Finally got past all those misfire codes and got the car registered. Drove it to work yesterday and everything seemed fine. On the way home I stopped to fill it up and shortly after the check engine light came on. Was hoping it was going to be the gas cap but pulled P0134 for no activity on primary O2 sensor. Surprised the reading would be inactivity since the car seems to drive fine. Any ideas on what to check out? Previous owner never had CEL so this is new.
Ugh - P0134 - Suggestions?
- Thread starter wlepse
- Start date
According to Toyota's recall info there are no open recalls...not sure if that means there were no recalls that applied or just none that haven't been addressed.
Either way I cleared the code and drove it to work this morning. Again the car seemed perfectly fine. While I didn't look at the O2 sensor signal specifically the one page shows my timing advance and it was being adjusted on the fly, so I think there might be a loose wire. Can't see how this sensor could give a fault of NO activity then function fine.
Either way I cleared the code and drove it to work this morning. Again the car seemed perfectly fine. While I didn't look at the O2 sensor signal specifically the one page shows my timing advance and it was being adjusted on the fly, so I think there might be a loose wire. Can't see how this sensor could give a fault of NO activity then function fine.
As mentioned above I drove the car to work today, about 40 miles and all seemed good. On the way home...about halfway...the CEL came back. Using the Torque app I pulled the same code plus pending faults P0133 and P2195. I also monitored O2 voltage and found it was pretty constant at 0.2V occasionally going up to 0.3V and it indicated it was running open loop due to sensor failure. I then cleared the codes and was surprised to see it indicating it was open loop due to insufficient temp. Within a few minutes the CEL was back.
So since the previous owner didn't have this issue it is either bad luck for me or has something to do with the other work I did recently. Both vac leaks or a bad PCV could cause this. I did have the intake out and replaced the PCV so this could be the case but the posting of insufficient temp makes me think the sensor is going. Can't see how it couldn't be up to temp after 20 miles...but not sure why it isn't throwing code for heater.
When I get some time I plan on verifying the vac lines, PCV and sensor voltage...any other suggestions?
So since the previous owner didn't have this issue it is either bad luck for me or has something to do with the other work I did recently. Both vac leaks or a bad PCV could cause this. I did have the intake out and replaced the PCV so this could be the case but the posting of insufficient temp makes me think the sensor is going. Can't see how it couldn't be up to temp after 20 miles...but not sure why it isn't throwing code for heater.
When I get some time I plan on verifying the vac lines, PCV and sensor voltage...any other suggestions?
Finally got a chance to take a closer look at this at lunch and think the sensor is dead. First thing I did was disconnect the sensor from the connector and check the ground. That checked out find with minimal resistance. Then I back probed the sensor connector and reconnected it to the vehicle harness. After turning the key to on I saw 0.1719 V and after running for about 5 minutes it was still at 0.17XX V. This correlated with what Torque was reporting so I suspect the ECM is OK. Also using Torque I monitored the vac and it is pulling a good vac so I don't think I have a leak or bad PCV or at least not bad enough to cause such a low consistent reading.
So I am about to pull the trigger and just order a new direct fit Denso unit...any other suggestions on things to check or recommend a different replacement?
So I am about to pull the trigger and just order a new direct fit Denso unit...any other suggestions on things to check or recommend a different replacement?
So far so good. Ran over to the auto parts store today for the other car and no check engine light but I will feel more confident when all of the emmisions checks are ready.
As a side note...I had borrow an oxygen sensor wrench from a friend, turns out it wasn't deep enough to clear the heat shield and get a good bite. So I took the top two bolts out for the heat shield...bottom ones were too rusted...then bent the shield up just enough that I could use an open ended wrench. Hope that might help someone in the same boat.
As a side note...I had borrow an oxygen sensor wrench from a friend, turns out it wasn't deep enough to clear the heat shield and get a good bite. So I took the top two bolts out for the heat shield...bottom ones were too rusted...then bent the shield up just enough that I could use an open ended wrench. Hope that might help someone in the same boat.
Well I have driven about 300 miles since changing the sensor and the light hasn't returned. The only surprising thing is the gas mileage has not improved at all. Tank prior to change was 30 and this last tank was 30.4. Seems a little low to me, my other ride (2011 Audi A4 1.8 w/ 240k) is getting 29 with same driving style over the same route. I would have thought this much lighter car without a turbo would be doing better.