What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Doubeleive

Wes
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Wes, is your engine modified? You need to see a tuner to cut back on the fuel. Your dumping fuel into your engine. Check a plug for color.
no mods other than a cai and ls7 throttle body, how could it be dumping fuel the short terms are -2/0 the long terms are 7, checked a couple plugs a couple weeks ago they looked fine, i didnt check them all, would a leak down test show anything?
 

ibfreeman88

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I'm still at 10psi currently. I did swap turbos from the original setup though so it makes power all through the rpm range instead of just up top. These LSA injectors are pretty high in duty cycle at full boost and 5-6k rpm's. As far as pwr/trq I honestly couldn't tell you it's been remote tuned since my first tuning debacle. I may throw on a dyno one day if there's a local dyno day just for giggles.


Turning up the boost? What PSI and HP/TQ you at now?
 

Doubeleive

Wes
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I think the MAF thinks your flowing a lot more air.

You should be pig rich....

A CAI can do that. How long has it been installed?
pretty much since I have owned the truck about 2 1/2 years

I have a autocal I bought i just haven't purchased a tune yet
 

swathdiver

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Well got my ****** gas mileage problem figured out for me

View attachment 230451

Late to the party, but I wonder what Wes, took out the cat? Sticky fuel injector? You can turn them on and off and check your fuel pump trims too. Your LTFTs @ 7, if they stay there for a long time are off. What's your alcohol content? If that number is off, you can reset the Fuel Trims and Fuel Composition and start her over again.
 

Doubeleive

Wes
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Late to the party, but I wonder what Wes, took out the cat? Sticky fuel injector? You can turn them on and off and check your fuel pump trims too. Your LTFTs @ 7, if they stay there for a long time are off. What's your alcohol content? If that number is off, you can reset the Fuel Trims and Fuel Composition and start her over again.
had 2 new magnaflows put on it today, the last couple times I looked the long terms were at 7 both times, it's weird that as soon as the p0430 code cropped up the mileage went up from 8 to 9.5, I can take a look at it some more tomorrow with the tech2
 

swathdiver

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had 2 new magnaflows put on it today, the last couple times I looked the long terms were at 7 both times, it's weird that as soon as the p0430 code cropped up the mileage went up from 8 to 9.5, I can take a look at it some more tomorrow with the tech2

If I remember right, a positive number is lean and that would explain why the cats are so hot. They heat up fast, especially when accelerating but cool down over a long run. For example, let's you accelerate onto the highway. The temps maybe get up to 1500 or so and then take 30 minutes to drop 200-300 degrees while maintaining that speed.

Since the cats are new, it is not unusual for them to throw a code within the first 100 miles, part of break-in period. Clear it and keep on driving.
 

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