Anyone have a Flex Fuel 5.7? (1 Viewer)

[kbahus]

Found a 2015 Tundra I am interested in purchasing but it is a flex fuel model, which I am not fond of. Backstory is I have been looking for a Crewmax for at least a year now with not much luck, this one checks the boxes minus the FFV aspect. Has anyone had issues with their FFV 5.7? Are you in a cold climate if so? I have read that people have issues, but want to confirm with my trusted mud sources.

 

[1911garand]

I have a 2012 5.7 Sequoia with flex fuel, in MN, so we also get the "special" winter blend fuel with extra ethanol.

No issues. I run standard 87, and the 15% 88 throughout the year. I have never used e-85 in the Sequoia.

It's a Toyota - rest assured they tested rigorously with FFV and it is the best in the industry.

Good luck!

 

[1911garand]

Also - I was an ASE auto tech for a decade, Polaris engineering for another decade. FFV vehicles / components never really created issues, it was the owners

I also have a 2017 Dodge Garand Caravan. It is a FFV - I regularly switch between 87, 88, and e-85 without issues.

 

[Jetboy]

What issues have you heard of?

I have a FFV 2016 Tundra. I live in Alaska. My tundra sees cold temps once in a while. Coldest I can remember is -30F and it seems to start and run without any issues.

Well - that's not entirely true, what I think is the timing belt tensioner idler pully is a bit squeaky for about 10 seconds when it fires up at cold temps. I have an new one, but haven't had a chance to swap it out yet to see if it goes away. But I don't think that's related to the FFV part.

But - what issues are people having in cold weather?

 

[kbahus]

I have read that the E85 sensor reads inaccurate percentages of E85 and needs to be recalibrated at the dealer, often over and over. It will read a high E85 percentage with no E85 in the tank causing the cold start to be very rich which creates a hard/no start situation. There are a few on the Tundra forums that report this problem, and others that have yet to experience it. It almost seems like the sensor loses it sensitivity and slowly adjusts the percentages in an upward trend until the truck won't start.

Tons of threads: Search Results for Query: ffv cold start | Toyota Tundra Forum - https://www.tundras.com/search/6221664/?q=ffv+cold+start&t=post&o=date

 

[Jetboy]

Interesting. I've never heard of that. I didn't actually even know that there were FFV and non-FFV options when I bought it. I assumed all tundra 5.7s were the same. I haven't had so much as a stumble on startup with mine. It's at about 90k miles now. I also don't know if it has ever seen a tank of ethanol fuel. Most likely not. I bought it in Utah where there is no E85 that I know of and then drove it to Alaska where there also is no E85 available anywhere I know of. It most likely has never had a tank of E85 unless it happened on a road trip to the midwest at some point.

Is E85 still available? I thought that that was gone since I don't see new FFV models anymore.

 

[kbahus]

It is good to hear that yours is trouble free. E85 is still a thing here in the midwest, there is even an ethanol plant in town. E85 prices are the same as pump gas so there are no benefits though. If the government didn’t subsidize E85 it would be gone I am sure.

 

[mdw83fj60]

It is good to hear that yours is trouble free. E85 is still a thing here in the midwest, there is even an ethanol plant in town. E85 prices are the same as pump gas so there are no benefits though. If the government didn’t subsidize E85 it would be gone I am sure.

Thought I would share my two experience. Had a 2012 Tundra 5.7 Flex Fuel , and randomly one winter ( live in Midwest) it started hard starting and gas mileage plummete. Took to dealer and they fixed for free I guess there is a TSB about this, don’t remember exact problem but they said they had to reflash computer because truck “thought” it was running on E85 but I never once used it. I now have a 2017 Tundra w/ 5.7 no Flex Fuel option. Two years ago same systems, took back to dealer and told the service writer about the TSB so he looked it up and found it. This time they flashed the computer, replaced fuel pump and some fuel lines. Service writer said even though I have the no FF 5.7 the computer still had some how “thought” it was running E85. Either way they fixed it both times.

 

[kbahus]

That is wild. Hopefully I don't have any issues, I picked the truck up yesterday. Worst case is a buy Techstream, which I have been putting off for a decade or so, and reset the values on my own if the dealer won't take care of it.

 

[mdw83fj60]

The second time it happen I did have to nudge the service writer to look up the TSB. But once he did no problems, and either time never happened again. Also when it did happen the trucks started really rough but once warm didn’t notice anything other then extra crappy mpg.

 

[Jetboy]

@kbahus just for your info - this was yesterday at -22°F. I did a video on how mine does in cold starts in Alaska. It had sat out overnight. Normally it's in my heated garage. This was with a remote start so I could shoot the video. It's just a boring truck start. Just give you a little piece of mind maybe. I don't think I could tell the difference between negative 22 and 75°.

 

[kbahus]

I haven’t had an issue yet with the new truck, started just fine even after sitting for a week and when the temps were below zero. I am not going to worry about it.

 

[AZBoatHauler]

Can confirm the ethanol sensor issue - I’ve had to reset mine twice.