I have a 2000 GTP I've owned since new. Recently it started acting up under boost. When the motor is cold it runs like a scalded dog. Once it warms up it about loses all power. Ran a scan with HP Tuners today and getting a couple of codes here. 0300 for Engine Misfire and 0171 for Lean Bank 1.
Hooked a vacuum gauge up and all hoses are pulling 19 inches of vacuum. Fuel pressure is around 40-41 at idle and in the neighborhood of 50 or more at RPM.
When it start spitting in popping I'm also getting knock retard out the waa-zoo. If I take the blower belt off it seems to run good, of course with no power. Never did a scan with no blower belt.
Here's an HP Tuners snapshot at WOT. TPS is at 100%, rpm at a measly 3,976, MAP is reading 164, MAF is 23 lbs/min, injector pulse width for boat banks is at 17.9, timing advance is at 4.5 with KR at 6 peaking as high as 9. LTFT is at 7 and STFT is at zero. Looking at the LTFT and STFT histograms after the scan they are both trying to add fuel like crazy.
And, the laptop just went dead... So any ideas. I was leaning toward the fuel pressure regulator but not to sure now. Is there something on the charger that adds fuel when under boost? I'm leaning toward a lean condition, but haven't a clue on the cause.
