Story of Ethanol.

Now, before many of you said 87 has worked well for you, yes, I know, but this is what happened to my truck and I've been keeping an eye on it for almost 12months.

I picked up the Tundra in November of 2020, everything was fine, but once a while the idle in park/neutral would fluctuate, not enough to bother me, and I used 87 from big name stations, while avoiding Costco gas like the plague (it caused other cars to knock/misfire).

As time progress, it gets bit more apparent, it would go from 800-850rpm dip down to 500rpm, doesn't matter the weather,cold start or hot start, a/c or no a/c, as I began to tow more, the mods started as well, to be safe, I use 91 whenever I can, but it would fluctuate the idle 70%-80% of the time when in Park/Neutral

It started to really bug me in the last few months that the truck would do this, I felt like driving a big cammed pushrod engine.

So I began trying to solve this issue, after lots of time and some money involved, Toyota claims its due to water condensation in the fuel system, as they had the truck for a bit and discovered when it did that, it was random misfire, but here's the thing, it does not store codes, Toyota actually had to send an engineer to look at this, so drained the tank and they did what they had to do.

Right now I'm sticking to Shell 91 (as it claims to have no ethanol) and so far so good.

Just want to share this story, I don't know if this will completely solve it, but I'm crossing my fingers.

 

Thanks for sharing the specifics of the situation. For a number of years there has been a problem with Phase Separation when using ethanol. That is usually tied to the vehicle sitting for extended times, but not always. If nothing else, it gives owners information that can be helpful when troubleshooting engine issues. Sometimes the "backyard mechanic" will dismiss things without every investigating.

 

Thank you for this. And where do you see that Shell 91 has no ethanol? all the shells in my area have that sticker that says "may contain up to 10% ethanol".
All I've used is shell 87 since i got the truck a month ago.

 

I searched extensively on the forum on this issue, and like you mentioned, sitting and FFPV were the top results, but my truck is not a FFPV nor it sits, the longest it sits on the driveway is about 2 days.

I use https://www.pure-gas.org/ , also Toyota engineer spoke to me about Shell in Ontario (Canada) doesn't use ethanol on the V-power (octane 91).

 

Around Austin, only 1 station has non-ethanol gasoline and its costs $.60 extra per gallon, Ouch.

So I use ethanol treatment stuff in all my small engines and autos that sit around a while before the fuel is used up (I have 4 autos between wife and I so its tough to drive them all enough when I work from home in the first place).

There are many, many varieties out there to choose from that do the same job basically yet I've learned to go with this one because it works and is much less expensive than most:

$22 Star Tron Enzyme Fuel Treatment Concentrate, 16 Fl. Oz. – Treats up to 256 Gallons – Rejuvenate & Stabilize Old Gasoline, Cure Ethanol Problems, Improve MPG, Reduce Emissions, Increase Horsepower

https://www.amazon.com/Star-Tron-En...nt+and+stabilizer&qid=1634244037&sr=8-1-spons

Luck all.

 

I haven't heard of costco gas being bad....i've been using costco 91 octane 99% of the time in the truck without problems.

ethenol content seems to be a geographic thing. in CA, basically all gas has ethanol.

 

I use https://www.pure-gas.org/ , also Toyota engineer spoke to me about Shell in Ontario (Canada) doesn't use ethanol on the V-power (octane 91).[/QUOTE]

Thank you, I guess vegas does not have any ethanol free gas stations here haha

 

You might want to see if Toyota will replace the alcohol sensor. Flex fuel vehicles have a sensor to tell the ECM what fuel is in use. It can be defective, but still within range. If the sensor is sending varying signals, the mixture and timing could shift fairly quickly and cause odd symptoms at idle that aren't evident at higher RPM's. I had a GM flex fuel pickup a few years ago and the sensor went out. GM wanted $650 just for the part. I finally found a company with a part that would bypass the sensor for $100, but that prevented using E-85, it became a regular gas only vehicle after that.

 

I've used Puregas.com and Boostane...I'm not sure it's worth the cost of using Boostane every tank...unless you're ONLY using 87 and it's been giving you issues...I'm incredibly impressed with real fuel and THAN Boostane on both performance and MPGs...not that MPGs matter, but I do get better efficiency when only using non-ethanol fuels...

 

Your area might be different but all of the stations around all get their fuel from which ever refinery is running the specific grade that day. It was the same down in the California Bay Area as well. So the Costco by me is using the same fuel as Chevron. The only difference is that the Chevron driver dumps a bucket of additives in before hitting the road. I also know that the same Costco uses up to 3 double tanker trucks of fuel per day. Fresh fuel is the best fuel.

 

I have noticed this. especially last night. I fill up at Costco and have noticed the idle shutter, and the truck is used daily, I've filled up at other stations and also noticed the shutter at full stop, Park and Neutral. Down time may be 18 hours at most..

Eitherway I took my 93 Lexus SC400 to the 76 station and added about 5 gallons of Premium gas (91 CA). Once I got to work I gathered my stuff and started my walk of shame to work, but quickly noticed a heavy smell of alcohol in the air and I was the only one that had arrived at that point and time.... So I may need to take a look at Shell's premium since I've also noticed it slighly on Costco more like a light sulfuric acid type smell and no, it wasn't my mother in law..... but not as heavy as 76....

 

Most of time yes, they do get from same distribution centers, but they add their own mix of detergent during loading, this is from what I've seen when my brief stint in oil/gas.

If you read up bmw forums, a lot folks have issue with rough idle and misfire with Costco gas on turbo engines, when we had our STi , it would misfire at idle, tried it on a modified 328i, it would misfire under load, since then I never bothered with Costco gas.

I'm keeping a close eye at this, do you guys know if techstream will provide live diagnostic to monitor misfire?

 

In Western Canada, almost all stations have no ethanol in their 91. Petro-Canada (Suncor) is the only one that I know of. The "up to 10% ethanol" applies to 87 (and mid-grade, which could be up to 5%). I'm not sure why they dumbed down the stickers lately because they used to have a separate one for each grade.