Stacked Tuning?
 

Hello,

Spent the last year building a 7.3 for a friend. Rebuilt Longblock, GTP38R Turbo, Adrenaline HPOP, UDP(Unlimited Diesel Performance) 1.5 Injectors, Hydra Chip, unlocked tunes through Riff Raff. All seemed good at first. Finally get the tunes loaded on the chip, and.....She smokes. At all times. Worse than a lot lizard and a free carton of Lucky Strikes. Even in modified stock, it smokes a little at idle, and any throttle at all causes obscene amounts of smoke. Anything beyond modified stock and it only gets worse. Other than that, it drives and idles fine. But way too much black smoke to drive realistically. Swapped in the stock injectors and it's right as rain. The injectors are new. Well new rebuilt. IPR and ICP look fine.

Finally, the question. Unknown history of truck. Reason for rebuild was a cracked piston. Prior to rebuild the truck appeared stock. No chip has ever been used. But this thing ran really strong for stock. I'm wondering if previous owner had programmed a tune and never returned it to stock. Would that mess with the Hydra? Does the chip start with the existing fuel and timing maps in the PCM and add to them, or does it use it's own entirely? Could a pre-existing tune jack up the baseline for the Hydra tunes?

If so is there any way to tell? Any way to re-flash to stock?

It's a 2001 Automatic.

Anytime a "chip" is physically installed on the PCM, the tuning on it will override whatever tuning is flashed on the computer. Whatever is flashed to the PCM already (stock or otherwise) becomes null when a 4-bank chip such as the Hydra is installed.

I'm confused, What are you trying to say?? :doh:

Messing around. Got it. Thank you for making this perfectly clear. I'd already decided I'm sending the injectors back to have them bench tested anyway for piece of mind.

cleatus12r is correct. The Hydra will override whatever is in the PCM, so that shouldn't be an issue. If you want to send your tunes list over to support@phptune.com, I'd be happy to double check the tunes list to make sure you have the correct files.

If you get the injectors tested and you've still got issues, give us a shout!