Do I need a 93 octane chip to run 93 in an emergency?

[Eric Stage I]

Can I get away with running 93 as long as I don't boost it or do I need a 93 chip. Trying to figure what I need if I run across a situtation where I can't get E-85 on a trip.

In an emergency, no problem. As soon as you start the car up on 93, and it goes back into closed loop, the BLM and INT correction will automatically pull fuel out. No adjustments necessary. It will be rich for a minute at first, but the chip can automatically pull the full 30% back out based on the stock O2 readings. It won't be perfect, but you can drive it around fine. Even up in boost, it will just be rich, but if you have the wideband correction enabled in the 6.1 chip, it will lean it out automatically. It's best to stay out of boost though until you get right tune back in.
Regards,
Eric

 

[696]

In an emergency, no problem. As soon as you start the car up on 93, and it goes back into closed loop, the BLM and INT correction will automatically pull fuel out. No adjustments necessary. It will be rich for a minute at first, but the chip can automatically pull the full 30% back out based on the stock O2 readings. It won't be perfect, but you can drive it around fine. Even up in boost, it will just be rich, but if you have the wideband correction enabled in the 6.1 chip, it will lean it out automatically. It's best to stay out of boost though until you get right tune back in.
Regards,
Eric

Thanks for the info Eric. I have the 6.1 chip so I won't have to switch a thing...excellent

 

[Eric Stage I]

Most chips will have enough range in the BLM and INT to get you home safely.

 

[696]

If I throw 93 in the tank, make it home and put E-85 back in will it return to my "E-85" settings if I never adjusted the chip?

 

[jdpolzin]

The computer corrects with the O2 sensor so as long as the chip is able to adjust enough for the difference in fuel, it's going to do it on the fly. Your always going to have your "E85 settings" so that will be a constant. When you use 93 octane with the E85 chip, the O2 sensor will see that it's running fatter so it will pull fuel enough to compensate.

 

[696]

Clr, got it.

 

[Ttype6]

Most chips will have enough range in the BLM and INT to get you home safely.

What is the lowest BLM number a person would see on his scan tool if your chip removed fuel to its full limit?

 

[Ttype6]

If I throw 93 in the tank, make it home and put E-85 back in will it return to my "E-85" settings if I never adjusted the chip?

Yes ,but now it will start very lean. I might just barely run,but once closed loop operation begins it will add fuel until it's correct again. The thing to do when you go back to E85 is disconnect the orange computer wire at the battery to reset the computer. Then re-connect and start the car and you'll already be there.

 

[BIGPSI]

What is the lowest BLM number a person would see on his scan tool if your chip removed fuel to its full limit?

104 on the Blm is -20% . not sure if the ECM will adjust that far

 

[Ttype6]

Thanks for the info Eric. I have the 6.1 chip so I won't have to switch a thing...excellent

If you run your car down to fumes and fill up with 93 it will be soooo rich. I'm not sure it will run,not to mention all the carbon you'll introduce into the oil. If you run down to empty,you'll probably still have a gallon of E85. If you add only a gallon of 93 to that and let the car learn with that 50/50 mix it will start leaner and will be able to correct fully in closed loop. Then fill up or add what you'll need to get home or to more E85. It will adjust to its full capability but I'm unsure if any chip can adjust the full 30%. If you had a Translator and any chip,you would surely have enough adjustment with the Translator base fuel knob turned to the 10% lean setting.

 

[Ttype6]

104 on the Blm is -20% . not sure if the ECM will adjust that far

Yes,that is correct.I'm pretty sure they can all do that.

 

[696]

Eric said his chip can pull -30% of fuel then things will be fine. I have already bumped my settings up on "factory settings" on my chip, I don't want to reset them by disconnecting the orange wire. The 6.1 chip self adjust so I should have to do anything for it to pull the fuel.

 

[Ttype6]

Eric said his chip can pull -30% of fuel then things will be fine. I have already bumped my settings up on "factory settings" on my chip, I don't want to reset them by disconnecting the orange wire. The 6.1 chip self adjust so I should have to do anything for it to pull the fuel.

Run it out of E85 and fill it up with 93. Start it up and see what you think. After the chip relearns,run it out of 93 and fill it up with E85 without re setting the computer. Start it up and see what you think.

 

[Eric Stage I]

There are 2 fuel trims, short term and long term (INT and BLM). In the stock chip the lower BLM limit was 105 (-18%) and the INT was 100 (-22%). These trims are both applied together, so it could pull up to 40%.

The BLM is the one that gets "remembered" for the next startup. The INT is reset to 128.

In my chips, I tend to set the lower BLM limit to 115 so it can't pull so much fuel in case of a sensor failure. But, combined with the INT, it can still pull 30%.

Keep in mind, I'm simply trying to say that in an emergency situation, you can put in some pump gas to get you where you need to go. Ttype6 is right, it would be better to use a smaller amount of pump gas mixed with the E85 so the fuel trims don't have to be jerked around quite so much. The Translator is also a good way to bump the fuel around.

 

[Eric Stage I]

I also agree it would be good to reset the ECM, so the relearn goes a little smoother. So make sure you have any other chip settings written down somewhere in case you need to punch them back in.
Eric

 

[jdpolzin]

If you run your car down to fumes and fill up with 93 it will be soooo rich. I'm not sure it will run,not to mention all the carbon you'll introduce into the oil. If you run down to empty,you'll probably still have a gallon of E85. If you add only a gallon of 93 to that and let the car learn with that 50/50 mix it will start leaner and will be able to correct fully in closed loop. Then fill up or add what you'll need to get home or to more E85. It will adjust to its full capability but I'm unsure if any chip can adjust the full 30%. If you had a Translator and any chip,you would surely have enough adjustment with the Translator base fuel knob turned to the 10% lean setting.

Just FYI becuase I have run E85 almost completely out and then filled up with 93 on quite a few occasions, the car starts fine and runs fine. It actually doesnt run that rich after the ECM learns. Prior to giving the ECM time to learn, it does run a little rich but not bad enough to make the car run or idle poorly.

 

[jasjamz]

Just FYI becuase I have run E85 almost completely out and then filled up with 93 on quite a few occasions, the car starts fine and runs fine. It actually doesnt run that rich after the ECM learns. Prior to giving the ECM time to learn, it does run a little rich but not bad enough to make the car run or idle poorly.

J...let it go. It will go downhill from here and information from a chip maker has been provided.

 

[jdpolzin]

J...let it go. It will go downhill from here and information from a chip maker has been provided.

Just trying to give my experience to help.

 

[Ttype6]

Just FYI becuase I have run E85 almost completely out and then filled up with 93 on quite a few occasions, the car starts fine and runs fine. It actually doesnt run that rich after the ECM learns. Prior to giving the ECM time to learn, it does run a little rich but not bad enough to make the car run or idle poorly.

I'll have to let my car run out and add 93 and try it. I did go from 93 to E85 once and let it run until it stalled and didn't refill and restart until the next day. If the car is warmed up during the change it might be more forgiving. I'll post results.

 

[jdpolzin]

I'll have to let my car run out and add 93 and try it. I did go from 93 to E85 once and let it run until it stalled and didn't refill and restart until the next day. If the car is warmed up during the change it might be more forgiving. I'll post results.

You know, I think it also depends on where your getting your gas from. On te Power Tour this year, we had some running issues with our gas chips in different states. Iowa gas was fine, Texas gas didnt like our cars, Oklahoma gas was ok but not the greatest. I think temp also plays an important role of course. It was freakin HOT in Texas. This was with a gas chip but I think it would play an important role in either set up.