Okay did some reaserch for you on this code and I hope this helps a little bit
"What does that mean?
Basically this means that an oxygen sensor in bank 1 detected a lean condition (too much oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1.
Note: This DTC is very similar to P0174 (
http://www.obd-codes.com/trouble_cod...en-sensor.php), and in fact your vehicle may show both codes at the same time.
Symptoms
You will more than likely not notice any drivability problems, although there may be symptoms such as a lack of power, detonation (spark knock), and/or a hesitation/surge on acceleration.
Causes
A code P0171 may mean that one or more of the following has happened:
The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters (K&N, etc.) can cause the MAF to become dirty if the filter is over-oiled
There could be a vacuum leak downstream of the MAF sensor.
Possible Solutions
Possible solutions include:
In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
Inspect all vacuum and PCV hoses, replace if necessary
Check for a dirty fuel filter and proper fuel pressure"
It sounds right to everything you have said about ur car, ohh
and btw DO NOT use octane booster, it damages the spark plugs and wears down the seals on the pistons, so yeah u have siad you used it, dont, it will woid warrentys, due to "trying" to increase octane with Chimicals. and such. so its very bad, worse case senrio u might have to pull out pistons and rehone the cylinder walls.
Hope this helps a bit. ill try to answer more questions if you have any.
Elvis
