After flooring(wot) my car for the 1st time at 10,000 miles, breaking it in perfectly with patience. Always changed the oil after 3,000 miles using Mobile 1 5-30. Changed spark plugs every 10,000 miles along with cleaning filter. Always checked my tires and alignments. The car is a beast runs great like no other banged up srt4 on the streets. Full gas tank always ran about 240-260 miles. After 50,000 miles this year ive been getting horrible mpg. 170-200 miles per tank!!!Yes and this is babying it without hitting 1 psi of boost, and shifting around 2000-2300 rpm till 5th gear.
Im throwing no codes. I changed both O2 sensors. Ive changed my whole brake system thinking i had a brake issue. YES I only use 93 octane gasoline.

Mods:
AGP wategate
AGP motor and tranny mounts
Mopar bov
Mopar short throw
Greddy turbo timer
Greddy catch can
MSD wires
3" exhaust
3" full cat-less exhaust
ATI brake system
AEM short ram Intake

wategate set at 15 psi.

Help please. I need suggestions.

 

i wouldn't doubt its from gas formulations changing, also where you purchase gas, sometimes i kinda think maybe the 10% on gas pumps for ethanol for the max, is actually for the minimum lol but if theres more alcohol in the gas your car would get less mpg, if you have no check engine lights, and haven't changed anything, like gone to a s1 pcm, and have new O2 sensors

 

I only use Chevron Gasoline. Shell gave me 150-170 mpg same goes for Mobile. Chevron is the best Ive had.

 

Well your using good gas then, kinda odd your mpg has dropped so much, do you do more city driving than before? I know mine does really well on the highway, but in town is horrible

 

id ensure there are no codes, put the key in the ignition, turn it on, off, on, off, then turn it on and look at the odometer it should say p**** or pdone, pdone means no codes. also maybe check and make sure your airfilter is ok, and check your plugs, something else to try would be unhook the negative on your battery for about 10 mins then hook it back up, that should reset the pcm, that way it is in learning mode and maybe that will help correct your problem.

 

I checked for codes. all it says is DONE ---------
Im going to check my fuel filter on Monday morning. Do you think that this has to do with my wastgate due to quick spooling. I dont see my gauge boosting but my bov sounds like its always blowing off under boost. This is extremely irritating i want minimum 230 per tank city driving. Yes i only drive in the city.

 

have you always just driven in the city? because it only takes about 10 gal to fill my srt up so if you get 170 per tank and it only takes say 10 gal thats still 17mpg which is good for in the city i think they were rated at 21mpg city so i would say 17mpg isn't bad at all as far as your quick spool all SRT's spool really quickly stock, just due to the size of the turbo, if you still have the stock gauge it could just be broke, i know most people say the stock gauge is junk, mines off 2-3psi with the car off, so your gauge may just be broken

 

check your thermostat to make sure its working properly. if not it will not go closed loop and run rich wasting fuel. just did mine this week and gained back approx 4 mpg