How long can I go with P0136 code?

so I bought my truck a week ago and have been driving it a bunch and even gone on a shakedown trip. Done a thorough once over with all fluids, brakes etc. I’m leaving for Oregon tomorrow and of course my check engine light comes on tonight. Code says O2 sensor bank 1 sensor 2. I’m relieved it’s nothing major and have no problem fixing it, except I’m leaving in the morning. I usually put 8-900 miles on my trip to Oregon and back. Is that fine to go ahead and go and change it when I get back? As I understand it, it’s just the sensor that checks the cat so it shouldn’t affect engine parameters? Anyone know?????

 

I drove about a year(15k miles) before repairing mine. Its been a few years and the truck is still running solid. No problems. You should be ok.

 

You'll be fine as PHM said. You may want to plan on replacing all 4 as preventative maintenance depending on your mileage.

 

Gas mileage may vary with that sensor...but, not sure that’s a concern with this vehicle.

 

my dad has been running his tundra for 6-7 years or more with a bad O2 sensor. MPG is a little worse, but drivability is just fine.

 

Oh my god that would drive me nuts! When I was a kid my dad went years without changing his windshield wipers just because he wanted to see how long they would go. At least that’s what he said LOL. It was just a smeary mess in the rain.

 

Depends on what it is. A P0136 just tells you that the sensor is reading unexpected readings, not directly implying that the specific sensor is bad. Down stream O2s are what is considered "dumb" and just work off of a 0-1V signal. All they are doing is making sure that the cats are cleaning correctly. What becomes a problem is if the front AF sensor is bad, but not bad enough that it's faulting itself out, but can be seen in the secondary O2s. Then your catalytic converters become at risk. Which is ridiculously expensive to fix.

Also... don't listen to this advice. If MPG is decreasing, it means its using more fuel. Fuel washing cylinder walls of oil and creating unnecessary premature wear. Not to mention the rest of the areas that need oil getting fuel soaked.

 

The story is actually that my dad brought it in to his mechanic to get it replaced and the guy replaced the wrong one and just left it, and my dad needed the truck right away and just never got around to fixing it.

sure it's using more fuel, but I really doubt losing 1-2 MPG is really going to make a difference with fuel washing the oil off the cylinder walls.

This truck has 205k on it and it's been driven like this for the last 50-75k. if it was going to be a real issue it would've a long time ago. It doesn't get any worse MPG than running bigger tires.


That being said, it's much cheaper in the long run to just replace the O2 sensor, but in the short run, no biggie.

 

Thanks for all the advice. Just drove it to Oregon and the light didn’t even come back on yet. (I cleared it last night) I disconnected the battery the day before to clean the terminals and one was really bad. Could that have something to do with it? Also I got 16 mpg and I drove 70-75 the whole way including the mountains above Redding. I’m feeling pretty good about that just as a whole. Does that sound about right to what others are getting?

 

Good luck with the project. Make sure you try replacing the oxygen sensor by lifting the front, removing the wheel, removing the little chunks of rubber between the engine and the inside of the fender - sensor will be right there. If you try going from under the truck, with the socket and extensions, you won’t have enough leverage. I’d try lots of PB blaster , sensor socket - the type that can be used with the breaker bar - and the longest breaker bar you can get.

Anyway, mine were seized and wouldn’t budge with PB Blaster, heat, chisel - I had to remove the exhaust manifold and replace it with a used one because it just wouldn’t come out.

Just as I repaired the passenger side and passed emissions, driver side tossed a code as well. I have the new sensor, but I’m reluctant to start the process because if it doesn’t work, it will take me 5-7 hours to remove the manifold on the drivers side. Not something I want to do in 30-40 degree weather.

 

Its possible you had an electrical gremlin due to corrosion. Drive it some more and see if the check light comes back. Or pay a shop to test the truck.

As far as MPG on long distance highway driving you are right in the average. I have 285/75/r16 tires and get about 16-17 doing 55-75mph. City MPG is 9-12 depending.