O2 Sensor trouble. Heaters? Help? (1 Viewer)

[scottm]

Oxygen Sensor trouble. Heaters? Help?

I had a check engine light, and the following codes:

P0135 (Powertrain: H02S Heater Performance Bank 1 Sensor 1)

P0141(Powertrain: H02S Heater Performance Bank 1 Sensor 2)

P0130 (Powertrain: H02S Circuit Closed Loop (CL) Performance Bank 1 Sensor 1)

P0133 (Powertrain: H02S Slow Response Bank 1 Sensor 1)

I replaced both O2 sensors with Bosch universal sensors, the check engine light didn't come on for a day, now the light is on and same codes are back. I have a ProScan, laptop-based OBDII scanner, and the sensors look like they're working normally once up to temp. Cold, the system runs in open-loop control of the engine, not using the O2 sensors. It goes into closed-loop control when the engine is hot and running well above idle. Research tells me the exhaust isn't hot enough at idle to run the O2 sensors without their internal heaters. The O2 sensor heaters are getting power and ground at the connectors at cold idle, as they should. I checked the front sensor heater wires, 3.6 Ohms resistance, that seems normal, and confirms the sensor wiring is OK. I'm beginning to think it has nothing to do with the O2 sensors, since no symptoms have changed with new sensors. What else can cause these symptoms? I just drove seven hours on the highway with no problems and good mileage.

The local dealer has two FJs for sale, color and options I want. Wife has given the nod. I feel it would be a downgrade, but my frustration is building. Help?

 

[MLX450]

It might be the Bosch universal sensors you used. Did you have to splice the wires or just plug and play? I think the OEM ones are made by denso.

 

[cruiserdan]

I replaced both O2 sensors with Bosch universal sensors

I rest my case.

 

[scottm]

It might be the Bosch universal sensors you used. Did you have to splice the wires or just plug and play? I think the OEM ones are made by denso.

Spliced them, but that's not brain surgery, and the splice connectors supplied are very nice. I've already verified the connections are good, and the signals from the sensors look normal. These codes come up at startup when the heaters are needed. I suspect a wiring fault somewhere isn't allowing adequate power to the heaters, but there are few common connections for the two heaters. Maybe a weak ground at the Engine Control Module, or weak power at the common power source coming from the EFI Main Relay. Those are the only common points in the system.

 

[IdahoDoug]

Hmmm. Try googling "Bosch Universal O2 sensors" and "problems". I just did it and spent about 10 minutes bouncing from forum to forum hearing about problems, and people giving up and getting an OEM one. Problem solved.

DougM

 

[cruiserdan]

I double-rest my case.

 

[RavenTai]

Dan, if you don't mind what is the ball park smart shopper on 2 o2's for a 96? (95-97 same?)

I thought I had read it at some point but I cannot find it now

 

[cruiserdan]

About a hundred bucks a rattle.

 

[Hondo]

How about for the 93/94?

 

[cruiserdan]

Same price, different parts.

 

[Vitesse_6]

Now the BIG question....how much were the Botch* universals?
Its amazing how an item can effect the running of a vehicle, It must be that time of year , I have replaced 2 on 2 different vehicles






* yes I ment to spell it that way

 

[RavenTai]

Now the BIG question....how much were the Botch* universals?
Its amazing how an item can effect the running of a vehicle, It must be that time of year , I have replaced 2 on 2 different vehicles

from about $60 to $150 each for flanged ones depending on where you shop. plus you have to splice them in. if they work it would be somewhat of a dolar savings, if they do not work it would be money down the drain.


Sounds like it is running well, sounds like you have done what should be done troubleshooting wise, could the signal be just a little off from what the computer is expecting?

did you try wiping the computers memory? (pull EFI fuse or battery) maybe a relearn of the trim will help?

could it be a intermittent bad crimp in one of the splices? maybe give them a good solid pull?

(reaching)

 

[IdahoDoug]

One forum guy did mention re-doing (soldering?) his connections and it fixed something.

DougM