So this is my conclusion to the P0170 code:

Things to check that WILL FIX THIS PROBLEM (If it doesn't I don't know what to tell you):
1. Vacum leaks
2. Map signal
3. Maf signal
4. Intake leakes (ie: injector seals, turbo tubing. etc
5. SECONDARY O2 SENSOR !!!!! (Clean or replace this for sure, most likely the cause) This was the mystery for one of my cars.
6. Primary 02 sensor
7. Check Fuel Pressure

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01.5' Black 1.8TQM
01' Red 1.8TQM

Turbo's- The lag is there to give V8's a chance.