Can a dmax forget?

[Dirty1actual]

What's up yall coming to ya from Alaska!!! I'm still figuring out this site and the duramax I bought a few months ago so forgive my ignorance. But here's a question for the diesel yodas out there ok the plastic resonator thing on my ride cracked sometime recently and right before that I borrowed a buddies hypertech tuner for the weekend to see if I wanna buy it (it's a hundred bucks thought whyyyy not) anywho so I put the level 2 tune on it and I'm thinking ok this is sweet nothing crazy but I know it's there and at some point I must've been scootin down the gravel roads too much and cracked the resonator then drove another 200-300 miles just sucking air straight into the turbo and the only reason I noticed was the truck started to feel like it just forgot the tune no codes, no lights, just felt stock again so I popped the hood and found the crack. Now my question is would that much air goin without the MAF knowing cause that to happen? And stay that way even after I fixed the leak with a scrap yard resonator? I reinstalled the tune and it feels good again

 

[paint94979]

Get a plumbers cap for it... My guess is you have become used to the extra power as a level 2 hypertech program is extremely mild to begin with

 

[Dirty1actual]

See that's the thing I didn't even have a chance to get used to it. I put the tune on it then drove out to the sticks and down a few miles of dirt road more like trail haha then on the way back and for a few days after It really felt like the tune was just gone. So I put a new resonator on and reprogrammed the level 2 on it and it feels sweet again

 

[paint94979]

Hmmm once the tune has been flashed there is no way for it to revert back to the previous set of maps that are no longer in the ECM...

 

[Akers]

Getting more air flow than the maf was reading may cause a drop in performance but it'd have to be a big ass leak.

 

[Dirty1actual]

the entire part the bolt goes through was broken off so a hole about the size of a golf ball is it possible the ecm compensated for that undetected air and stayed that way even after the new resonator was put on? It took a few hours of driving for it to get sluggish would it have taken that long to fix itself?

 

[THEFERMANATOR]

The tune doesn't just forget itself. Once it's flashed into the ECM, it is there. Sounds to me like a PICNIC, problem in chair not in car. Not trying to be mean, but it happens. When theres a problem some people will swear it is still there even after fixing it. I tuned an 06 for a guy and he swore his milage dropped down from 21 when I first did the tune to 16 after a month. Brought it to my buddies shop and left it. I went over, scanned it, verified everything was working, and left(didn't touch the programming in any way). He swore after that it ran like crap, misfired, and was only getting 12. Brought it back to my buddies shop, he left it, my buddy didn't even call me, after 3 hours passed he called him to come pick it up, and he said it ran better than ever. Keep in mind he had complained 3 times about problems and poor performance, yet I never touched the tuning or anything on the truck, didn't even pop the hood, and he said it was fixxed. Your mind can play tricks on you, and it happens more than we want to admit.

 

[Dirty1actual]

So the big old hole behind the MAF wouldn't have anything to do with getting close to half the fuel mileage I should get and it running like shit? I already know that an air leak behind the MAF can cause those things I just thought it was strange it stayed running shitty the entire day even though the leak was fixed I figure the ecm had adjusted itself or something like that haha I don't know though outside of an old sbc or windsor my experience is minimal but I literally took it up and down the road burying my foot in it before I tried retuning it and it just wasn't the same until I reprogrammed it

 

[dirtydmax]

Have you changed your fuel filter lately?Plugged filter can cause it to run Shitty.Just a thought.

 

[PhilsLB7]

Get a plumbers cap for it...

Yep . . . do the Home Depot performance mod. Get a 2" Fernco pipe cap and get rid of the plastic resonator. They are prone to crack (or worse in your case) so take it out of the system.

 

[1ATony]

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