Check engine - p0136 Code - Question

[benjicon]

Hi guys,

My 98 SR5 threw up a check engine light last weekend, coincidentally after I had my fuel pump replaced. I ordered a Wi-Fi OBDII scanner, got Torque Pro app, and got the code out tonight. Code p0136, "O2 Sensor circuit malfunction, bank 1, sensor 2".

I did some searching and read this thread through which did help....

http://www.toyota-4runner.org/maintenance-detailing/52109-h02-sensor-bank-1-sensor-2-p0136-code.html

But my question is this, the check engine light turned off after a day, does this mean the problem rectified itself? I've been driving it for a week now and no more check engine lights. Should I proceed with purchasing a replacement sensor, or wait until the error pops up again?

Thanks.

 

[MONTYMTB]

Hi guys,

My 98 SR5 threw up a check engine light last weekend, coincidentally after I had my fuel pump replaced. I ordered a Wi-Fi OBDII scanner, got Torque Pro app, and got the code out tonight. Code p0136, "O2 Sensor circuit malfunction, bank 1, sensor 2".

I did some searching and read this thread through which did help....

http://www.toyota-4runner.org/maintenance-detailing/52109-h02-sensor-bank-1-sensor-2-p0136-code.html

But my question is this, the check engine light turned off after a day, does this mean the problem rectified itself? I've been driving it for a week now and no more check engine lights. Should I proceed with purchasing a replacement sensor, or wait until the error pops up again?

Thanks.

If you cleared the code and it hasn't come back, I would just wait and see what happens. I think the link you posted was about a 4th gen - you'll get better results if you filter your search to the 3rd gen section:
http://www.toyota-4runner.org/3rd-gen-t4rs/149799-alternate-search-toyota-4runner-3rd-gen-section.html

 

[stir_fry_boy]

My rule with check engine lights is verify twice then replace, unless something is obviously wrong. Keep driving and see if it returns.

 

[benjicon]

If you cleared the code and it hasn't come back, I would just wait and see what happens.

Thanks guys.

I just popped back down stairs, scanned again, cleared the code from the ecu, then fired it up again. No code popped up.

I'll keep and eye on it as suggested, if the code goes again I'll bite the bullet and get the new sensor.

Cheers, Benny.

 

[Buckaroo]

FYI....info from FSM regarding p0136.....note the specific criteria to set the code (engine warm and >31mph) and that it uses 2 trip detection logic meaning it has to happen again after key-off to set the code. If it occurs once, it will not light the CEL but it will be stored as a pending code.

DTC No. P0136
CRITERIA: Voltage output of heated oxygen sensor remains at 0.45
*1V/0.4 V*2 or more or 0.60 V*1/0.5 V*2 or less when vehicle is
driven at 50 km/h (31 mph) or more after engine is warmed up
(2 trip detection logic)
*1: California Spec.
*2: Except California Spec.
POTENTIAL CAUSES:
_ Open or short in Heated oxygen sensor circuit
_ Heated oxygen sensor

Buckaroo

 

[WallyWest]

I had that one myself, same symptoms. It would pop up now and then. Got more and more frequent.

It's possible the code points to a bad O2 sensor, but what it's literally telling you is the circuit the sensor is on has stopped working. In my case it was badly frayed wiring at the connector that the sensor plugs into. If you wind up in the same boat don't let the parts guys talk you into buying and replacing the entire wiring harness from the sensor to the engine bay. You can buy the connector itself with four wire leads and solder it into place, cost me like $10 to fix.

 

[benjicon]

I had that one myself, same symptoms. It would pop up now and then. Got more and more frequent.

It's possible the code points to a bad O2 sensor, but what it's literally telling you is the circuit the sensor is on has stopped working. In my case it was badly frayed wiring at the connector that the sensor plugs into. If you wind up in the same boat don't let the parts guys talk you into buying and replacing the entire wiring harness from the sensor to the engine bay. You can buy the connector itself with four wire leads and solder it into place, cost me like $10 to fix.

Thanks Wally, Good advice.

FYI....info from FSM regarding p0136.....note the specific criteria to set the code (engine warm and >31mph) and that it uses 2 trip detection logic meaning it has to happen again after key-off to set the code. If it occurs once, it will not light the CEL but it will be stored as a pending code.
Buckaroo

Buckaroo, thats really interesting, I had the car out this morning, and was travelling over 50kmh. When I get it home tonight I'll throw the scanner back on and see if its recorded another error. Really great advice.