15-16mpg...not cool

[ctrlraven]

So in the next week or so I think I am going to change my plugs and see if that helps me get better gas mileage, any certain plugs anyone used and noticed an increase in gas mileage and what gap should I get?

This 250-280 miles per tank poo is a pain in my butt. I did notice I got better mileage after I installed GM COP Connectors a few months back but I have yet to hit 300 miles on a single tank full up before the low fuel light comes on. Yes I get on it from time to time but I do usually 80% highway driving and the rest scooting around town. When I took my car down to the eastern shore in MD from central MD I put on about 149 miles with 1/8 take used, during my normal weekly driving I get that must mileage with about half a tank. I fill up at the same gas stations Shell or Hess whichever is less.

[Matt Johnson]

15-16? I'm getting 12-13 daily city driving.

[jawz101]

12-13 sounds about right when I am tuned and have the CAI. 15-16 when I'm stock

[O's Fan Rich]

Holy crap... I'm getting that in my daily driving and thats with #132 boosting up pretty often. I got 22 hwy last time I checked.
Check your driving habits too. There are some good sites to get info on stretching your mileage just by making adjustments to your right foot.
http://www.edmunds.com/advice/fueleconomy/articles/105501/article.html

I LOVE #1. It fits so well with this site.:rolleyes:

[SergntMac]

I average 18 MPG in the #1x the last time I checked, and I'm getting 22 MPG city from the #3 MM. Maybe some of y'all need to look at your tranny shift schedules and TC lock-up? I changed mine back to OEM stock, and I'm pleased with my performance and MPG.

Honestly though, you're not going to enjoy much of both at the same time.

[merc6]

in d.c I get lucky to see 200 as the light comes on. when I hop on 95 to go somwhere out in bum falk va, I expect to see 160 miles before the needle moves from F.

[MM03MOK]

Just made a trip to NH and back and got 20.11 mpg. I'm very pleased. That's with a Trilogy and 4.10s.

[RF Overlord]

So in the next week or so I think I am going to change my plugs and see if that helps me get better gas mileage, any certain plugs anyone used and noticed an increase in gas mileage and what gap should I get?What plugs are you using now and how many miles are on them?

I see you have one of Dennis's tunes so check with him, but normally he recommends plugs 2 steps cooler than stock and a 180° thermostat. If you're still using the stock plugs and 'stat with his tune, the knock sensor may be pulling timing, which can lower your fuel economy.

Gap should be stock (.054)

[SID210SA]

I just came back from Corpus to San Antonio, filled up before I left and got 140 miles out of the first 1/4 tank, cruise set at 79 mph. 1 stop at a rest area to use facilities and punched it leaving rest area. My gas milage has gone up since I moved. I used to live 3 miles from work....I now live about 16 miles from work and get an extra 20-25 miles out of a tank. Short drives really do kill you gas milage.

[SergntMac]

BTW...I guess I should mention that Chicago Has been a ethanol town for about 20 years. This may account for 1-2 MPG differences, moreso if we don't go through any seasonal change in blends. Same old crap gas year 'round.

[ctrlraven]

What plugs are you using now and how many miles are on them?

I see you have one of Dennis's tunes so check with him, but normally he recommends plugs 2 steps cooler than stock and a 180° thermostat. If you're still using the stock plugs and 'stat with his tune, the knock sensor may be pulling timing, which can lower your fuel economy.

Gap should be stock (.054) Stock plugs and 55k miles on them as far as I know. I don't know anything about cooler or hotter plugs, I do know a 180 t-stat lol. How do I figure out if a plug is 2 steps cooler?

[ctrlraven]

12-13 sounds about right when I am tuned and have the CAI. 15-16 when I'm stock Well atleast I don't feel left out on sucky gas mileage now :beer:

[ctrlraven]

Maybe I should just order the Denso plugs and t-stat from DR?

[RF Overlord]

I don't know anything about cooler or hotter plugs...How do I figure out if a plug is 2 steps cooler?Stock Motorcraft plugs have the number 32 in them...22 is 1 step cooler and 12 is 2 steps cooler. You'll have to pull one to see if they've been changed.

The stock equivalent in Denso is IT16...one step cooler is IT20 (there is no IT18) and 2 steps is IT22 (yes, the numbering goes backwards from Motorcraft).

Dennis sells them all, so ask him which is best for your application.

[bradical]

After reading several of these MPG threads, I started carefully tracking my results. Over 15 tankfuls I can report that I am enjoying 17.7 MPG around town average and 23.3 MPG average on the highway.

My car is stock with the following exceptions: PHP intake spacer, K&N CAI, Pro-Guard rear panel (I know everyone calls it a skid plate, but in my book a skid plate is a hefty piece of steel used to slide over rocks.) I got the above results driving very conservatively.

[bagpiper]

I have 4:10 gears,180 stat,and Denso plugs.I average 16.6 or 300 miles a tank full.

[Badger]

16-18 City and 22-24 hwy.
One good reason for the lower city is I dip into boost much more often with AC on. Good side is I don't really notice the AC drain on the engine.
Drove my old 98 CV the other day and the AC drag was driving me crazy. Had to keep pushing the pedal down to get going.

[Dragcity]

I just stopped keeping track....

I'm driving the V-12 Jag this week and am getting 17.2 MPG on the highway.

Seems we have a huge range, from 17 to 23 MPG. That's a lot, 35%...

There seems to be a LOT of variables too. Ethenol, operating temps, driving habits, mods, X-Cal settings... To many perameters....

The new Camry's are nice....

[Lou]

I average 18 MPG in the #1x the last time I checked, and I'm getting 22 MPG city from the #3 MM. Maybe some of y'all need to look at your tranny shift schedules and TC lock-up? I changed mine back to OEM stock, and I'm pleased with my performance and MPG.

Honestly though, you're not going to enjoy much of both at the same time.


Mine is stock and I get 18 city and 22 hwy. Once [and only once] I got tad over 24 MPG and 400 miles on a tank before the lihht came on.

[silverfrost1]

My car is stock with the following exceptions: PHP intake spacer, K&N CAI, Pro-Guard rear panel (I know everyone calls it a skid plate, but in my book a skid plate is a hefty piece of steel used to slide over rocks.)

Pro-gard (TM) is a skid plate if installed "outie" over the edge. I see most people install this inside the bumper edge for appearance sake, negating the skid plate function. Mine is an "outie".

[RF Overlord]

Actually, it's not really a "skid-plate" at all since it's just a thick sheet of flexible plastic. Its major purpose is to keep air from being trapped behind the rear bumper and causing "ballooning" at highway speeds. It also has the minor function of helping with bumper sag. It does the job just as well whether installed as an innie or an outie.

[studio460]

What are you guys complaining about? I get 10 miles per gallon! Stock rear end. Almost stock everything. 'Course, I do floor it at almost every light.

[SamF]

What are you guys complaining about? I get 10 miles per gallon! Stock rear end. Almost stock everything. 'Course, I do floor it at almost every light.

I am in the throttle too much I think ;)

Over the last 1100 miles of basically suburban driving (lots of short trips, lots of 2 lane cruises, some highway) I averaged 15 mpg, Highest mileage over five tanks, 16.5, lowest 14.1.

[MENINBLK]

Pro-gard (TM) is a skid plate if installed "outie" over the edge. I see most people install this inside the bumper edge for appearance sake, negating the skid plate function. Mine is an "outie".

If it is made of plastic, it is NOT a skid plate.
Once you backup over something you'll wish you had a REAL skid plate...

[94_302]

Have you tried loading your x-cal 2 in economy mode? I recently bought an x-cal 2 SF. City I would say is between 17-19mpg and Highway is between 22-24. (I'll need to run a few more tanks through to get this down a little more)

[Bradley G]

Holy crap!
You may as well get blown.
That is the worst mileage I've ever seen in my car.