Decrease in gas mileage

[ryan1stinger]

I’m in California and I’ve always used 91 octane. Im the original owner of a 2018 Stinger GT2. Average MPG has decreased from 22 to 17 MPG. Car only has 30k miles.

This decrease in gas mileage was noticed after Tork ECU tune (now back to default/OEM file) as well as mods (snow meth - not used anymore, FMIC and catback exhaust).

Don’t drive my car hard anymore, therefore I don’t understand why my gas mileage has decreased by 20%. I know there are numerous reasons that can account for reduced fuel mileage including spark plugs. My OBD2 scanner shows no issues now, but when I had the Tork ECU tune dialed up I was experiencing 02 sensor issues on the catalyst.

Given the price of gas these days, I want to get to the bottom of this issue sooner than later I may end up uninstalling all mods and go back to factory. I’m going to take it to my mechanic to have checked.

Anyone else experiencing this and what caused it?

Thanks.

 

[Stinger305]

I have a 2018 (Premium, so gas mileage will be different) and fwiw I noticed my gas mileage has gotten better after around 18k miles. The Stinger does really well with highway driving but can be a hog in the city where I mostly drive. I'm also always in Sport mode as I've noticed that being better for mileage than Normal. Sorry I can't really speak to your situation.

 

[ryan1stinger]

Thanks. Yes, definitely better with highway driving, but like you, mine is mostly city.

 

[nhcowboy28]

Bruh. I was lucky to get 16 mpg city driving.

Part. Out.

 

[Cosmo]

California "green" low volatility summer gas. Mine drops 2 hwy & 3 city. The tuner guys I know recommend you go easy on the turbos with this crap too.....and not just Stinger's, all turbos.

 

[BrocStar]

I’m in California and I’ve always used 91 octane. Im the original owner of a 2018 Stinger GT2. Average MPG has decreased from 22 to 17 MPG. Car only has 30k miles.

This decrease in gas mileage was noticed after Tork ECU tune (now back to default/OEM file) as well as mods (snow meth - not used anymore, FMIC and catback exhaust).

Don’t drive my car hard anymore, therefore I don’t understand why my gas mileage has decreased by 20%. I know there are numerous reasons that can account for reduced fuel mileage including spark plugs. My OBD2 scanner shows no issues now, but when I had the Tork ECU tune dialed up I was experiencing 02 sensor issues on the catalyst.

Given the price of gas these days, I want to get to the bottom of this issue sooner than later I may end up uninstalling all mods and go back to factory. I’m going to take it to my mechanic to have checked.

Anyone else experiencing this and what caused it?

Thanks.

Hello, Sorry to hear about this. I just purchased a 2023 GT2 and I am also in CA. SD to be exact. I was wondering what area you are in? I am looking for a good shop/ mechanic that can help me with some mods and or basic maintenance. Can you spread some knowledge in this area?

 

[ryan1stinger]

I’m in the SF area, so can’t help with a local mechanic. I’m not mechanically inclined, however many of my mods (e.g. led rear reflectors, badges, led door sill scuff plates, carbon fiber dash, carbon fiber console, upgraded FMIC, air intake pipes, scoops, RC chip and pedal tuner, spark plugs) I was able to do myself with the the help of folks on the forum, YT or the Stinger manual I linked on this site.

For the Meth install and cat back I had my local mechanic and muffler shop install.

What are you looking to do?

 

[ryan1stinger]

I changed from Sport to Comfort and mileage drastically increased. I thought I did this a while back and it had little impact. Even when not pushing the car in sport, mileage suffered. Must be due to lower gear at higher RPMs. Engine working just that much harder. In addition to that, I stopped adding boostane to the tank.

 

[ryan1stinger]

If not familiar with boostane, it increases the fuel’s octane level.

 

[BrocStar]

California "green" low volatility summer gas. Mine drops 2 hwy & 3 city. The tuner guys I know recommend you go easy on the turbos with this crap too.....and not just Stinger's, all turbos.

When you say go easy with this summer gas. What do you mean? Driving style. As in do not gun it? Or keep RPMs down? Just curious as I just got my stinger and only has 150 mile on it. Of course all my friends have been wanted me to haul ass to feel the speed. I hope I am not doing damage. Whatcha think ?

 

[BrocStar]

I’m in the SF area, so can’t help with a local mechanic. I’m not mechanically inclined, however many of my mods (e.g. led rear reflectors, badges, led door sill scuff plates, carbon fiber dash, carbon fiber console, upgraded FMIC, air intake pipes, scoops, RC chip and pedal tuner, spark plugs) I was able to do myself with the the help of folks on the forum, YT or the Stinger manual I linked on this site.

For the Meth install and cat back I had my local mechanic and muffler shop install.

What are you looking to do?

I was looking to do CAI and possibly an ECU tune. But after thinking about it and talking to the dealer I decided to stay stock. If I do decide to do the CAI I would also do exhaust.

 

[ryan1stinger]

When you say go easy with this summer gas. What do you mean? Driving style. As in do not gun it? Or keep RPMs down? Just curious as I just got my stinger and only has 150 mile on it. Of course all my friends have been wanted me to haul ass to feel the speed. I hope I am not doing damage. Whatcha think ?

Maybe I’ve been lucky, but I’ve pushed my turbos hard without incident. I purchased my 2018 new and it has 32k miles. I’m in CA.

 

[ryan1stinger]

I was looking to do CAI and possibly an ECU tune. But after thinking about it and talking to the dealer I decided to stay stock. If I do decide to do the CAI I would also do exhaust.

Tried the Tork ECU tune, but my car didn’t like it. I know folks that had success.

If I were to go back, I would keep mine stock.

 

[BrocStar]

Tried the Tork ECU tune, but my car didn’t like it. I know folks that had success.

If I were to go back, I would keep mine stock.

Sounds good. Not even CAI? I figure because I live in the desert parts of the year the CAI would help with the engine performance and keeping it cool. I am having reservations about doing the intakes and snorkels. I know one thing leads to the other. LOL

 

[ryan1stinger]

No truer words uttered. Not even CAI.

 

[ryan1stinger]

Sounds good. Not even CAI? I figure because I live in the desert parts of the year the CAI would help with the engine performance and keeping it cool. I am having reservations about doing the intakes and snorkels. I know one thing leads to the other. LOL

No truer words have been uttered. Not even CAI.

 

[BrocStar]

No truer words uttered. Not even CAI.

I guess you can always go back to stco right ? Just keep the old parts and there you go.

 

[BrocStar]

Can I ask you why you’d go back to stock if you could go back ?

 

[BrocStar]

No truer words have been uttered. Not even CAI.

Can I ask you why you’d go back to stock if you could go back ?

 

[Rodtheviking]

If not familiar with boostane, it increases the fuel’s octane level.

I use Lucas Octane Booster with 92 round here and I'm happy with 17ish average.