[sixstang]

Getting somewhere between 17-19 mpg in the city, is there any way i can improve this through some simple mods?

[chiefsmustang20]

Get a GT or Cobra lol

[sixstang]

Originally Posted by chiefsmustang20 Get a GT or Cobra lol

Not an opportunity that I have at the moment....

[v6 stunna]

a Cold air intake..change ur spart plugs and wires..maybe your coil to. get highflow cats.. and a lighter foot. a tuner

[mcqueen]

How long has it been since you had a good tune up? Also, like stunna said, you might need to be easier on the gas pedal. I know I get around 18mpg around the city because I'm usually pretty heavy on the throttle, but just the other night I took a little trip to a nearby city. Went about 50 miles round trip, filled up just before I left, and my gas gauge barely moved (it didn't plummet when I got in my car today like it sometimes does either). 75mph all the way, ~3k RPMs in 5th gear (4.10 gears), cruise control, stuck behind semis on on-ramps so I couldn't mash the gas pedal and go. Usually that trip would easily burn nearly 1/4 tank of gas for me with the way I tend to drive.

[SALEEN961]

I was getting 18-20city in my car before I put it away for the winter, but my clutch is to blame for that. You can't slip my clutch at all so I have take off quick in 1st and that gets me in the habbit of keeping my foot to far down until I reach my cruising speed. I'm getting about 25mpg on the highway.

I'm hoping a Fenderwell Intake, Divorced Duals, and an SCT Tuner will at least bring my highway mileage up a little bit. I'm tired of my fake duals with this y-pipe into y-pipe bs that Flowmaster made as a bolt-on for my car.

[6ER THEN I 8ER!]

Fuel filter is most likely clogged....cheap to fix so do it lol

if that doesn't help check your spark plugs and wires, air filter, and maybe test your gas...pour some of it in a mason jar and see if it seperates showing water in it...

[SALEEN961]

It looks like from the factory a '99 5-Speed V6 was rated at 20/29, but the EPA rating has been revised to 17/27. An '04 5-Speed V6 was rated at the same 20/29 from the factory but it's mileage rating has been revised to 18/27, probably because it has IMRC.

Factory and revised EPA fuel economy ratings can be found at: FuelEconomy.gov

[jakeabraham]

my car seriously gets like 15mpg city, and I don't feel like I drive too fast or anything. I mean occasionally I like to hit the gas a little but its not like im flooring it off every red light. idk wtf the problem is.

[SALEEN961]

I've noticed that when I run cheap gas (Speedway, Marathon, Store Brand) I get 2-3mpg less then when I run BP or Sunoco gas. Most gas stations have the same prices whether they sell cheap gas or not so it may be worth switching brands to see if your mileage improves.

[MRKsD3]

I feel like my mpg had significantly gotten worse too... I just changed my fuel filter about 2 weeks ago... I have CAI, dual exhaust, and a tuner...

Only after the duals and the fuel filter that I noticed the mpg getting worse...

Spark plugs + wires maybe?! I still have the same ones since I bought the car... How can you tell that it needs changing already?

[MRKsD3]

Plus, I run 91 octane (tuner) so it's really hurting my wallet right now. Sometimes I think about going back to stock tune and put 87!

[Rich J]

^^^ I'd do it, especially if we do see $5/gallon prices on just regular 87 this summer.

As for the OP check out your fuel filter. I get SHIT for gas mileage (well use to, just fixed it yesterday) because of my 2 exhaust leaks on the same manifold. One crack on the manifold itself then a crack which ended up making the flange break right off the manifold causing me to have one open manifold... I was running pretty lean for a while so my engine kept dumping gas in to try and compensate for it.

[Dreamer]

How do you check for exhaust leaks?

Idk how any of you guys get 18 - 20 in the CITY. I get 14-15 in the city and thats IF im grannying the whole day. Maybe my "city" is a lil worst because its ny I red light after red light every 20 yards. And the traffic and stupid people that THINK they are cars that wanna run in front .... >_<

I was thinking of getting checked out as well but I feel like i get much better mpgs with my 93performance tune than I did stock. But I know race tune Im pouring gas like water.

[walt1120]

i think you guys should run 89 or so if you have a stock engine. i was a supporter of not wasting money on premium fuel unless you have mods that require it. 89 is definitely processed better than 87 and isnt that much more money.

as far as gas mileage tips:
try sea foaming the car
new fuel filter
new spark plugs
new air filter
run 5w-20 oil (if you dont already)
maybe even underdrive pullies

[Rich J]

I always run 89 now, when I first got the car I didn't. I always ran 93 lol. Now its all 89.

[MRKsD3]

With a tune requiring 91, is it ok to use 89? I'm thinking I might as well return to stock tune if that's the case...

But then again, 89-91... Only 10 cents price difference around here (at least), I think I'd rather stick to 91... No?

[Dreamer]

no NEVER go under the tune, its ok to go above never under.

Example. I have a 93 tune its BAD to use 91 but if i was running a 91 tune it would be OK to use 93 gas

[Dreamer]

double post..........

Edit: It woulda been smarter if i just wrote the post below this... here....oops

[Dreamer]

Originally Posted by torchredmustang With a tune requiring 91, is it ok to use 89? I'm thinking I might as well return to stock tune if that's the case... But then again, 89-91... Only 10 cents price difference around here (at least), I think I'd rather stick to 91... No?

depending on the tune that "10" cents might be alot more than you think.

Put it like this with 87 stock tune i filled up 12 - 13 gals everytime at 45$ give or take a dollar. Twice a week so that's 90$ a week

When I went to 93 RACE. Filling up 13 gals is now 50 - 55$ and with the RACE tune im filling up 3x a week if im driving everyday (remember im in NY its alot of CITY just to get to a HWY)

BUT

93 PERFORMANCE i don't burn so much, I fill up maybe once a week maybe twice if im partying everyday. So the increase (30cents) from 87 - 93 which only came up to an extra 5$ didn't seem like much until i was using race and noticing how much more OFTEN im filling up.

That's what you should take into consideration when switching grades. The 30cent extra wont make that much of a difference if you're still getting the same or even better mpg.