AmDWs6

So I've noticed that I'm getting really low mileage comparing to others here with a new tune full tank is able to get me to 170miles now half of the last quarter is left
I used to get a max of 11mpg 160miles
Car is 02 ws6 with 55 litre tank I know cause everytime I fill it up it nvr reaches 50 litre (some left over fuel)
I'm also using 95% fuel don't know what you guys call it
But most around here use 91 I suppose?

Anyway I just had the car retuned
Also throwing a code for the passenger side headers O2 "insufficient switching" and another code evaporative system small leak. Since the car was retuned now SES light is back on but I don't know what the code is.

Idea's?

Mod's -
Slp lid
Ls2 maf
1 7/8 3" full exhaust no cats
3" inlet dual 2.5" outlet magnaflow muffler
Monster Stage 3

Everything else is bone stock.

LS6427

iTrader: (2)

Insufficient switching is a failing 02 sensor. They run terribly rich when they are failing. Put a new 02 sensor in that position and your problem should be solved. But get a scan if you can to to make sure that 02 sensor is not switching properly.

rockauto.com and amazon.com usually sell the best 02 sensors made....Densos....for about $35.00-$45.00 each. SAME EXACT Denso sensors that the GM dealers sell for upwards of $180.00. They are identical........

.

AmDWs6

so i checked by the scanner and yes i have P1153 ONLY Bank 2 Sensor 1 Insufficient switching.
i've managed to get 180 miles out of a full tank 55 litre
making my mpg ONLY 12-12.5 SUX !
i have old O2's from my original Ws6 exhaust i'll throw one in there and see if its good enough, think that's ok to do or must get a new one?

Just FMI"for my information"
how much mpg could i get from a 55 litre tank running 95% fuel
and how same but running 91% fuel?

i live in the middle east 95% is only 2.65USD Per 10 Litre and 91% is only 2.12USD Per 10 Litre.

AmDWs6

changed the O2 DTC didn't pop, mileage still the same