Hello everyone,

I hope I'm posting in the right place and looking for some help. I have owned an Evo previously and it was strictly on e85, and I never switched it to 91.

I'm now looking at flying across the country and purchasing another Evo, and it is also on e85, but has a switch installed that it suppose to change it to 91. I'm looking to make a fun trip out of this and will be driving back to where I live instead of trailering the car or having it shipped. Being said, I obviously want to switch it back to 91 before I begin my travels.

My question is, how do I know the car has switched maps from e85 to 91? I haven't got exact details from the owner on this process other than there was a switch installed in the glove box that should toggle the maps, and it was installed by Fathouse Fab and was tuned by Fathouse Fab as well. The current owner has never taken it off e85, as it was installed during previous ownership.

Is there any obvious signs to look for that it properly changed maps?

Thanks in advance and pardon my newbness on this topic!

 

Laptop and really only way I guess is to log it and see what it's doing or I guess ask the original owner to demonstrate it for you

 

Its all pretty simple. There will likely be an LED light attached to switch like mine. The light may be on or off depending on how it was set up. My light if normally off when Im on the E85 map

Anyway, it should be toggled for the E85 map so make sure the tank is as empty as possible. Run the EVO until the tank is empty. The gas light will be on & run it another 15 miles or so after that

Then go & fill w/91 & after the fill, toggle the switch to the 91 map. You should here a distinctive change in engine tone. Run the EvO out of boost, as much as you can, for the first tank. After that, re-fill w/91 & all should be OK to hammer on it if you like

 

well it will run like complete garbage if your on the wrong map. E85 map with 91 will run insanely rich and bog like crazy

 

Or you could buy a jerry can and fill up with e85 and drive it back, maybe plot where e85 gass stations are, that's what I would do.

 

Oops, wrong thread LOL

 

Might depend on the tuner and shop that set it up. But like others suggested, have the owner demonstrate for you before you start this road trip.

I've been on my dual map for 4 years. Scot Gray of RRE set it up an easy toggle between maps:

With the car off and ignition on, push down the accelerator pedal. The check engine light will flash super fast. That means I'm in E85 mode.

Lift off and push the accelerator down again, and the check-engine light will flash much more slowly. This now means I'm in 91 mode.

Pretty simple and fool-proof. But definitely check with the owner to see how it was set up and the tuner that did the work. Good luck!

 

Thanks for the response, I was banking on my tuner being able to fly there with me but it just so happened he has other plans out of town for the next couple weeks.

The previous owner had given the current owner a print off of the instructions in which to switch it from e85 to 91 maps. I haven't been able to view those documents yet, but hoping overall that I'm really stressing about nothing and it'll all work fine. I just cant help but to worry about what disaster it could cause if they maps didn't switch for whatever reason and we drove all the way home on the wrong map, if we'd even make it home in that case. >_< So I'm hoping there are some easy ways to tell physically about the cars temperament that'll give it away.

 

TBH this trip is from NYC to AZ haha 2,000+ miles.... that'll be alot of planning lol. But if it comes down to it, I'll have to do that, or rent a trailer and truck and tow it back.

 

That's pretty damn cool, I really hope it is that easy to do in this car. I have witnessed some before that are like that process. I just do not know the process on this car, and it doesn't help I'm severe OCD/paranoid.

Edit: It was installed and tuned by FatHouse Fab in Indiana.

 

You wont make it to the first on ramp, let alone home if your running on the wrong map.

 

That's what I was suspecting too because of all the additional fuel, but I'm no tuner and don't know for sure. Glad all you guys are here to help me out!

 

Edit, sorry, I thought it was another person who posted.

So it will be more than obvious, and I'm stressing about nothing than hopefully.

Really appreciate all of your help!!!

 

Yah the car will barely run, if at all when your on the wrong map, and a check engine light will come on very quickly for fuel trims.

 

Ok sweet, good to know. Have you had this happen to you by accident before or witnessed it?