Fuel alcohol percentage relearn without going to dealer???

[slowride]

the victim is an 06 Tahoe with 5.3 flex fuel engine. Has only been run on either non-ethanol or the regular 10% ethanol gas. Im getting P0172 and P0175 codes, preventing me from getting it to pass inspection. My scan tool shows the fuel reading 46% alcohol content, which is obviously off for some reason. My research shows the high alcohol reading making it throw the rich codes. Apparently the alcohol percentage that the truck is reading can be reset to 0 or whatever with the right scan tool like the dealer has. Im trying to find out if there is a way to get it to readjust itself without having to take it in to the dealer or switching back and forth between E85 and regular gas to try to do it that way. Thanks

 

[drakon543]

have you tried unhooking the battery for 15 min and hooking it back up. i know with my 07 Pontiac they told me i needed to have them do a reset relearn. price was ridiculous so i did the work myself and just unhooked the battery. my friend who used to work at a different gm dealership at the time informed me that unhooking the batteey would trigger a reset relearn on alot of features in gm vehicles.

 

[slowride]

unhooking the battery didnt reset it but thanks for the reply

 

[Doubeleive]

you need to take it to the dealer, or any shop with a tech2 type scanner i.e. snaop on, etc.
or buy a vx diag nano about $100 online
or a tech2 clone $300 online
then you can go in and reset the trims takes about 60 seconds to do with the right scanner.

 

[Joseph Garcia]

If you do any work yourself on your truck, take Doubeleive's advice and purchase a Tech 2 online for $300, as that is probably close to what you will pay for the dealer to reset the truck. At least, for the $300, you will have a great diagnostic and reset tool that you can use for the rest of the truck's life.

 

[slowride]

looks like i prob will need to upgrade my current scan tool

 

[HiHoeSilver]

the victim is an 06 Tahoe with 5.3 flex fuel engine. Has only been run on either non-ethanol or the regular 10% ethanol gas. Im getting P0172 and P0175 codes, preventing me from getting it to pass inspection. My scan tool shows the fuel reading 46% alcohol content, which is obviously off for some reason. My research shows the high alcohol reading making it throw the rich codes. Apparently the alcohol percentage that the truck is reading can be reset to 0 or whatever with the right scan tool like the dealer has. Im trying to find out if there is a way to get it to readjust itself without having to take it in to the dealer or switching back and forth between E85 and regular gas to try to do it that way. Thanks

This happened to me before, but I got lean codes, because I was running e85, and it was showing 30% instead of 50+%

Two things I learned.

1. My buddy's snap on scan tool could reset the fuel composition.

2. Only reset it with normal gas in the tank.

 

[swathdiver]

the victim is an 06 Tahoe with 5.3 flex fuel engine. Has only been run on either non-ethanol or the regular 10% ethanol gas. Im getting P0172 and P0175 codes, preventing me from getting it to pass inspection. My scan tool shows the fuel reading 46% alcohol content, which is obviously off for some reason. My research shows the high alcohol reading making it throw the rich codes. Apparently the alcohol percentage that the truck is reading can be reset to 0 or whatever with the right scan tool like the dealer has. Im trying to find out if there is a way to get it to readjust itself without having to take it in to the dealer or switching back and forth between E85 and regular gas to try to do it that way. Thanks

Where do you live Dave? Maybe you live close to one of us that has one.

 

[Fless]

@slowride Yes, the Tech 2 should be able to reset it (with E10 or straight gas only in the tank as @HiHoeSilver said). Eric O shows how:

 

[slowride]

Im in NC near Greensboro. I went by several shops today and asked about their scan tools. 4 had the kind of upper end scan tools that would work but either tried to tell me to get a new gas cap or to clean my MAF sensor or something like that instead of even trying to hook it up and giving it a shot. The others either didnt have the right scan tool or had no clue what I was talking about. One guy even said that since it was a former police vehicle (its a PPV model) that they probably put the wrong computer back in it when they sold it, because they take out the high performance computer when they sell them you know. I had a friend of mine who knows one of the guys at the Chevy dealer call him to see what he said and he told me to add at least 7 gallons of regular gas and then drive it about 10 miles so it might reset itself. Now its reading 60% alcohol in the tank. LOL what a day