p1153 even with 2 OEM o2 sensors

TL;DR: The issue was the TSB reprogramming (not the O2 sensors). When I replaced the part a year ago, I likely installed "new old stock" that premature failed. The second replacement was maybe "new stock," which the ECU read differently? Maybe they aren't exactly the same? Either that or my car is running worse now for some other reason (old cats, worn injectors?) and that was tripping the code just over the unprogrammed ECU levels? Not sure exactly but at least getting the ECU updated, fixed the issue, not another O2 sensor. I am tempted to put the old (from a month ago) 02 sensor back in, but just assume not to mess with it at this point to prove anything to myself.

Long Version:

• Took the car to the dealership for diagnostics after all my efforts had failed. I was done trying to find the issue.
• They said the new AC Delco sensor I had installed about a month ago was bad, and quoted $330 for parts/labor/diagnostics. I let them do it, figuring if it wasn’t the issue, they’d need to address it again at no extra cost.
• Paid ~$330, drove a drive cycle, and the CEL came back on with the same P1153 code in <50 miles.
• Returned the car the next morning and pointed out (again) the TSB for this issue, and gave a full written list of all my previous repairs or tests that were noted above that were related. I also printed out the TSB and gave it to them as I was concerned they had ignored me on that topic the first time.
• This time, I pushed for the ECU reprogramming at no charge—minimal effort/cost for them. They agreed, reprogrammed the ECU, and.... it worked. After a drive cycle, the car passed emissions (Utah only requires CEL off and readiness checks).

In hindsight:
I could’ve pushed back harder initially when they suggested another 02 sensor, but I think dealerships, or pro mechanics, maybe they just distrust any home mechanics. I got the old, recently replaced, sensor back in the deal, and the ECU reprogrammed for "free". I figured the cost of the diagnostics and sensor install roughly equaled what the ECU reprogramming alone would’ve cost, so it’s a wash, and I keep the old sensor and my pride knowing I didn't have the Tech 2 Scanner tools to diagnose it any further or to reprogram it anyways and I was right the first time, just could not prove it without them doing the work. Took it for a 500-mile trip this weekend, with no issues. They also gave me a $50 service credit, so the next oil change is mostly on them I guess.

Thanks for the info on this. I figured it had to be something with the ECM, didn't think corrupted software was one of them!

anyone have the tsb to read?

was reflash part of the tsb?

j91z28d1 said:

anyone have the tsb to read?

was reflash part of the tsb?

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first post has a link

mattbta said:

first post has a link

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I. must have scrolled right by it.

wow, 2008 specific. that's pretty wild. good job getting it fixed. I would have never guessed a reflash ecm over sulfur

Wholly Ship! Small refinery exception for allowing greater amounts of sulphur than permitted in gasoline?!?!? Thus triggering a check engine light!!




I’m going to have my ECM reflashed even though this TSB says it’s specific to 08.

Just discovered my long cranks are related to a crank position sensor that never triggered a code for years, until it did.

I don’t think the gas here in Utah is 80 ppm sulfur based on the article link found below, and this doesn’t seem to be a “small refinery” issue. The state has made significant efforts to clean up Salt Lake City’s winter air. From the sounds of the TSB, it seems the dealership just adjusted the ECU limits to allow up to 450 ppm sulfur before triggering a code.

This might mean it’ll be much longer before I see Catalytic Converter or P1153 codes again, which is good in some ways. However, the downside is that my car may not be helping the inversion/pollution here in SLC. That said, it’s “legal,” and I only drive about 4K miles per year. I usually fill up at a Sinclair station near my house, so my gas should be well below the old 80 ppm sulfur limit based on the article at the bottom.

Maintenance is as follows:

• Oil: Supertech 5w-30 Full Synthetic High Mileage
• Additives:
  
  • 1/2 quart Lucas Synthetic Heavy-Duty Oil Stabilizer
  • Marvel Mystery Oil (in the last fuel tank before my annual oil change)
• Annual Mileage: ~4-5K miles with annual changes.

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If my fuel and oil shouldn’t have high sulfur content, doing some online searches it seems like my Catalytic converters may be on their way out, not surprising given the 250K miles. Luckily I guess I just bought some time for now without the CEL turning on again anytime soon. I guess I would much rather pay for the reprogram than get after-market converters even for $1K and then still have to do all the work....​

Four Utah refineries now produce cleaner Tier 3 fuels, and the fifth says it will soon

"Utah has five gasoline refineries north of Salt Lake City that produce most of the gasoline consumed in the state. The two largest, Chevron and Marathon, have been producing and selling Tier 3 gasoline since 2019. The next largest, HF Sinclair, says it has been producing gasoline below Tier 3 (7-8 ppm sulfur) since October 2021."

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