Need help with 1996 GST Gas Issue

[romeshs]

Hi guys..
i know gas mileage issues has many threads here, and i have searched almost all i think and havent found a solution for mine. So here goes..
i recently bought a 96 gst with an auto tranny.
i get about 150 miles to 13 gallons.
i have checked for boost leaks as some threads suggested,
but i didnt find any. my car is bone stock, with 69000 miles on the clock.
one issue i did find after going through the many threads was that one of the lines from my BCS had come off. the one that goes to the intake. i cleaned and plugged that back in. i also removed the restrictor.
i have the stock boost gauge on the dash so i dont exactly know how much boost im making, but under hard acceleration, the gauge almost hits the full mark on the gauge.
i have a problem with engine mounts as answers to a previous thread i had started, helped me to understand but i doubt thats the cause for the gas mileage issue.
ive checked everywhere i can think of for leaks but havent found any.
please help guys. this things driving me crazy. cant afford to out that much gas in the damn thing.
not to compare, but i get around 350 miles to 13 gallons on my other car, a 2009 lancer ex. 2.0.
please guys any ideas will help.
thanks in advance.

 

[Cabam]

That looks like the one i just replaced on mine just make sure not to use bosch cause some reason they dont work good on out electral system i went oem denso it was a coupe bucks more but worth it when i seen how much gas I started to save....

 

[romeshs]

Thanks bro.. Do you remember the part number of the denso O2 sensor you used?

 

[micha118833]

I believe that a stock engine and turbo should run a ngk bpr5es plug and a step above should run a bpr6es or brp7es plug which is a colder plug. and on up to bpr9es for very high powered turbos. gap them at 28