2003 Hypertech stage 2 and 31/2 inch exhaust with the cat gone, while hunting in Colorado going up hill towing a small trailer at 8,000 ft. it smokes like crazy !!!!, had a code for the Mass Air Flow Sensor, I had a K&N filter on it but took it off when the code started showing up, changed the MAS Sensor and it just smokes when stomping on the accelerator or under a load when pulling onto the freeway and then clears up, could the EGR valve cause this ??? truck runs fine and no smoking when idleing or just cruseing but as soon as I step on the accelerator it puffs a little black smoke then clears up, when I was in altitude it seemed to lose power and kill all the mosquitos for miles around !!

Less air at altitude, turbo takes longer to spool and has to spin faster to make the same amount of boost. The Hypertech tune is just over fueling the engine. Drop it back to stock and see how it behaves.

Later,
Stephen

Thanks, I reset the truck to stock settings and will try that, si9nce I live in Calif. it'll be a few months befor I can get to that altitude again, my Hypertech programmer detected 2 codes U1026 and U1024 one is for transmission communication error and one is for transfer case communication error anyone ever had these show up and any solution the these codes ???

I took my first dmax (03 LB7) up pikes peak a few years back and didnt notice any smoke. I wasnt pulling a trailer though.

Stopped in Elko Nevada on my way to Colorado last year Elk hunting when the engine light came on it ha a code for the MAS sensor, I've since changed the MAS sensor and the engine light has never came back on and this was since last October, I'm wondering if the Hypertech tuner is doing more haam than good and as far as a K&N filter I have one if anybody wants that thing !!! all it ever did was oil up the sensor, I''ve also read where the tubes running from the wheel wells to the tubo can wear through and cause problems ?????? the truck runs good and the injectors have been replaced, just trying to narrow down the causes, thanks for any information I can get

Communication error codes are usually related to a dying battery or corrosion on a battery cable.

Later,
Stephen