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Discussion Starter #1
Guys, I just installed the H&S Black Maxx, Full exhaust and AFE intake yesterday on a 2011 LML...and the performance so far is very dissapointing.

Snap WOT from idle yields minimal fueling and power sub 2500RPM is non-existent.
.. Once you hit 2500RPM, the power comes on but isn't very impressive from what I was expecting given the claimed DYNO #'s.

I had the privilage to drive another similarly equipped 2011 LML(but with a mini maxx) the same day... and they drove similar, with similar limited fueling and very weak sub 2500RPM fueling.
I'm thinking that they both have some sort of problem going on but I need some advice on where to look.

So far I reinstalled the download at least 3 times and went back over the directions with a fine tooth comb, finding nothing wrong there.

Could these trucks have a software issue going on or something stupid that's killing the performance?

Any help is appreciated!:helpHeyyaa



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We have seen very consistent dyno runs near 500hp from many of our customers. We also see high 13 second 1/4 mile times. The most common problem is when customers unplug the pressure sensor for the DPF. Do NOT unplug the electrical connection to this sensor or you will experience very limited power gains.

Make sure you follow the emissions delete instructions as they are posted in the instruction manual.

You can also use the "performance testing" software to test your tuning results. There is a 0-60 and a 1/4 mile testing option in there. Use them to verify that you are gaining considerable HP over stock.
 

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them new trucks must be freaking heavy. 500 rwhp hp and high 13's???? interesting
 

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Discussion Starter #4
We have seen very consistent dyno runs near 500hp from many of our customers. We also see high 13 second 1/4 mile times. The most common problem is when customers unplug the pressure sensor for the DPF. Do NOT unplug the electrical connection to this sensor or you will experience very limited power gains.

Make sure you follow the emissions delete instructions as they are posted in the instruction manual.

You can also use the "performance testing" software to test your tuning results. There is a 0-60 and a 1/4 mile testing option in there. Use them to verify that you are gaining considerable HP over stock.
Thanks for the reply!
I've been very impressed with H&S on several other trucks I've put it on so I felt sure there had to be something wrong here.
Thanks for the tip on the pressure sensor, I think I only removed the hoses and didn't unplug it but I'll confirm that.

I hope it's something that simple, that would be great!:drink
 

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Discussion Starter #5
PS> If it is unplugged and I plug it back in, do I need to reinstall the download?





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I had a similar problem. Make sure you didn't remove the rear most dpf sensor. I went through and re checked my installation manual. It says if un plugged it will cause reduced engine power. I plugged it back in and it runs 10 times better. Before I was only getting 23 pounds of boost. Now I get 28-30.
 

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mine has hit 35lbs of boost, never had any issues except defueling between gears which i think is a safety feature built in for the tranny which is nice to be able to still shift smooth.
 
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