it will also be stored in the ECU.
Acura can investigate and look at data logs to see whats up

 

So here is the result of the visit to the dealer today. They were able to see the code was logged for the front cat (which was just replaced) which showed it was not functioning right last week, but it is operating correctly now. Since the system turned off the warning lights (lack of a better descriptor), their assumption is that it might have been a random "snafu" that is unexplained. When they checked the systems today, everything is operating normally. While they admit that the following is an outrageous possibility, they said that it might be the replacement cat could have a manufactures defect in it. Now neither they or I really believe it, but it is a possibility. They checked the air fuel mixture and that is fine, as well as the PCV valve ( I think that is right), no other issues look to be an issue upstream of the cats. They thought the bad gas issue could be a trigger so they recommended that I use a different station from the same brand (Shell in this case), and try to use up this tank to as close to empty as I dare before filling again. Lastly they said that they have not heard of any other RLX, TLX, or MDX cars with the V6 nationwide with this problem so this is definitely a unique thing.

Everything is fine for now so if the same lights come on again, they will try to problem solve the situation at that time.

 

How I would play it as well.
reset codes to see if they were one time fluke, and if they come back, we know there is a serious problem.

here's hoping the codes dont come back up!

tip: it usually is a cycle of 20-30 miles before it'll trip the CEL again

 

Did you discuss the fuel mileage with them?

 

No answer on the mpg. I will monitor it and report back.

 

..use up a tank of bad gas..

I don't know a single tech that would advise that

What do you think G? @04WDPSeDaN

 

So I just completed another 110 miles on the same tank of gas, and returned 33.7 mpg for the trip. I have more driving this evening that will take me down to close to empty so I will refill then at a different station. The car is operating normally. I can't explain for the drop in mpg in the early portion of this tank. I have completed 325 miles on this tank with an average of 27.3 mpg but as of this morning that average was in the mid 25's I think. So the trip the morning improved the overall, but that is still way off from normal. I wonder if the winter gas mix is being used now? I think that was discussed previously that it degraded mpg too in addition to using the heat which means less EV mode running and more ICE mode running, thus the lower gas mpg from that alone. I will report more of my of my findings and we can debate what it all might mean. It is a puzzle.

 

it seems as if you are generally interested in what your car is doing.
grab the OBDII data logger and data log!

 

I'm not even going to tell you my fuel mileage.

I don't want to start a fight.

:-)

 

GK I think that the roads in your area promote higher mpg. My trip into NYC this morning produced 39.3 mpg until I turned left onto 30th street where it took me an hour to travel 8 blocks. By the time I got back onto the West Side Highway heading north the trip mpg dropped to 28.9 mpg but rose back to the 33.7 mpg when the trip was completed. Full disclosure, NYC is at sea level and I live at around 750 ft above that so the uphill aspect of the trip produced less mpg than the downhill portion. When I drive in NJ for long periods of time, I tend to see mpg in the 32 range. I will be in your neck of the woods over the summer and will see if my car responds to the roads like yours does and produce the same results. I suspect it will. You might also be a superior driver too.

 

Emptied the tank and ended up at 28.3 mpg overall. That is still about 2-3 mpg below normal. Everything seems fine for now.

 

That's correct, its never suggested to use up a bad tank of gas.

If the car is knocking / pinging due to bad quality gas, it does nothing good for the engine. There's only so much the knock sensor can do, but ultimately, a bad tank of gas always wins. I've experienced having a bad tank of gas before with some serious misfires and have dealt with it on the service end of customers having poor running conditions due to bad gas. MOST will drain the tank of bad gas and fill it with fresh (highest octane) gasoline. They also clear out the gas line and injectors / rail as well, before starting the vehicle with fresh gas.

 

I guess we have another one for the books here
Thanks G for your insight!

 

Maybe this was the true source of the issue? EE4Life posted this in the TSB thread.

http://www.urvi.net/forumfiles/SB/B17-019.PDF

 

I was just about to post the same thought......