p0136 Help (1 Viewer)

[mrsleeve]

Ok, I have a 97, it has been tossing an intermittent p0136 (bank1 sensor 2) Welp my down stream O2 is fused in tight and I have not had time to cut it out and rework my exhaust to fix it right. So I finally got tired of the light popping on every 100ish miles like clock work, and took the brand new denso o2 I have laying around and plug it in and ZIP tie up to the frame for now until I have some time to fix it right in a week or 2....

Well even with the NEW DENSO o2 ZIP TIED to the frame ghetto fix style I am still getting the P0136 about ever 100 miles..... I have looked over about 90%s if the wiring harness and dont see any thing obvious and dielectric greased the connector all to NO avail...

just wondering if anyone else has had something similar and if the got it resolved and if so what they found to be the culprit

Thanks guys
RJ

 

[BILT4ME]

It's a not-so old, but old thread.......

My 96 LC is throwing an occasional P0136 code as well as a P0401 code. Not always at the same time.
O2 Sensor and EGR.

I have an UltraGauge in the truck so I clear codes as soon as they happen to see how fast they come back, if at all.

This is my DD. I put on 15K-20K miles/year.

For the last 2 weeks, I have been making daily trips 75 miles each way on interstate / 2 lane roads.
Yesterday, it decided that it wanted to run rough when at 3300 RPM under load, OD off, cruise control on, going uphill. I could feel a jerking like I was hitting a heavy headwind or a clogged fuel filter.

Fuel mileage is averaging 11.5 MPG.

I thought this was odd, as I've been driving it regularly. The only thing I put together with this is that yesterday it was raining.

I'm wondering now if I have an O2 sensor plug getting wet and causing these issues and codes.

What I don't know, is how to interpret the O2 sensor monitoring I see while I'm driving. It appears to go to 115 (%? Units?) under full throttle and down to 2.8 completely off throttle and coasting downhill. This happens to be on sensor #2, as I don't have the #1 sensor being monitored on the page on screen.

Yes, I probably need to do an EGR diagnosis and do an O2 sensor check out, but I am looking for ideas.

I have new exhaust (5000 miles?)
Complete tune up was done 81K miles ago
(plugs, wires, cap, rotor, brakes, calipers, wheel bearings, radiataor, hoses, VC gaskets, spark plug tube seals, O-Ring, Oil Pump seal, crankshaft seal, tires.)

I installed new belts two weeks ago. I also did an oil change.

So:

What does the info on the O2 sensors tell me?
What should I check first?
What kind of oil should I use?
What are the best tires?
Is my Fitzer Valve broken?

 

[Maozebong]

for that code to set, the o2 voltage has to be below .1v for 30 seconds iirc. a good o2 cycles between .1 and .9 at a rate of 60hz at 2000rpm. a rear o2 should have the same cycling pattern as the front when engine cold and cats not warmed up.

low rear o2 voltage can be caused by exhaust leaks, a lean condition, and voltage shorts. the first two aren’t likely because you’d get a p0171 for the lean code and the front o2 would be very low cycling rate.

if the sensors are any decent, swapping front and rear will help eliminate if it’s the sensor or something else since the low voltage code will change to b1s1.

for the EGR, the whole system is checked by the egr temp sender. if you apply vacuum directly to the EGR by swapping hoses around, you should see the engine bog down or stall. if it doesn’t, clean the egr ports. if it does, check that the vacuum solenoid works (use 6p connector by fuel rail) and that the back pressure transducer is clean. replace if there’s carbon inside the transducer cap.

the surging and power loss sounds like a misfire. you said 81k miles on tune up parts? sounds like you’re due.

 

[BILT4ME]

for that code to set, the o2 voltage has to be below .1v for 30 seconds iirc. a good o2 cycles between .1 and .9 at a rate of 60hz at 2000rpm. a rear o2 should have the same cycling pattern as the front when engine cold and cats not warmed up.

low rear o2 voltage can be caused by exhaust leaks, a lean condition, and voltage shorts. the first two aren’t likely because you’d get a p0171 for the lean code and the front o2 would be very low cycling rate.

if the sensors are any decent, swapping front and rear will help eliminate if it’s the sensor or something else since the low voltage code will change to b1s1.

for the EGR, the whole system is checked by the egr temp sender. if you apply vacuum directly to the EGR by swapping hoses around, you should see the engine bog down or stall. if it doesn’t, clean the egr ports. if it does, check that the vacuum solenoid works (use 6p connector by fuel rail) and that the back pressure transducer is clean. replace if there’s carbon inside the transducer cap.

the surging and power loss sounds like a misfire. you said 81k miles on tune up parts? sounds like you’re due.

So, what are the "units" for the numbers I'm seeing on the O2 sensor readouts on my UltraGauge? I know it's not volts since we're hitting in the hundreds.

But what does it all MEAN Bazel?

I'm guessing it's voltage shorts causing the issue since this is the first time I've been able to pinpoint directly after a rain.

Yeah, I'm about ready to do the next full service, but I want to "fix" the issue before I just throw more at it. It will hit 300K on Tuesday, maybe Monday.

 

[Maozebong]

So, what are the "units" for the numbers I'm seeing on the O2 sensor readouts on my UltraGauge? I know it's not volts since we're hitting in the hundreds.

But what does it all MEAN Bazel?

I'm guessing it's voltage shorts causing the issue since this is the first time I've been able to pinpoint directly after a rain.

Yeah, I'm about ready to do the next full service, but I want to "fix" the issue before I just throw more at it. It will hit 300K on Tuesday, maybe Monday.

i believe you’re looking at “o2 correction” which is usually displayed as a percentage.

if you have a voltmeter you can check the o2 at the firewall diagnostic connector.

the reason i suggest that the misfire is a problem is because the rear o2 has no effect on how the engine runs, it’s only there to monitor cat efficiency. also suggest that bc you said it’s worse when wet, a sign of bad plug wires. copper plugs last about 30k and platinum is ~60k. pull a plug and check the plug gap and you’ll have an answer if you need them or not.

egr isn’t stuck open, bc you’d have a p0402 for excessive flow.