It seems that ever since 2-3 months ago I've been having to fill up more and more often. I seem to average like 13 miles to the gallon or something and I was wondering if anyone knows any common replacements or fixes I can do?

I drive a 5 speed and I shift at 2k or less everytime...I also try to coast to the stop whenever I anticipate one.

Thanks,
Brandon

I would check your air filter, MAF, and IAC for dirt

Stop shifting at 2k...

If you shift at 2000 rpm, then you'll be starting out in the next higher gear at 1200 rpm or so. That is way below the bottom of the powerband, and well into an area inefficient operation.

Shift at 2800-3000 so as to get the "starting point" in the higher gear up to 1800 to 2000 rpm.

What sort of driving do you do, how long are the trips you take? If you are driving mostly in city/heavy suburban stop-and-go traffic, on short trips, the best you're going to see will be 16-18 mpg.

Really?? Thats interesting, because I use to shift at 3k like I did when I learned how to drive stick on small 4cyl cars and I've been told that V8's don't need to rev that high because the torque is already there and it seemed to make sense to me...


And yeah everytime I shift it goes down to like 1200 or so. Could that be the reason for my poor mileage? Sometimes I donno if I should shift or not when I am cruising at a constant speed at like 2k and etc... What if I'm crusing at a constant speed at like 2500 on 3rd? Is it ok to shift down then?


I live in LA so it's mostly street driving but also a lot of freeway driving at times. My freeway mileage seems to be ok though...


Well I live next to school and I don't work so the only driving I do is just leisure I guess, or running errands. If weight is any factor in this then I practically have nothing in my car... Also took out the spare tire & related. I usually take very short random trips...A typical "longer" trip would be to chill with my friends at their school which is like 10 miles away.

What cliffy is trying to say is that you are lugging the engine. The car will use more gas believe or not when you are trying to get the engine out of a low rpm range. Just think of it like starting in 2nd or 3rd gear and trying to take off. Your car will burn more gas by trying to get the car up to speed. There is a shifting spot in each gear that will create the best opportune to get the best gas mileage.

Please take this in a spirit of poking you in the ribs...

All the way to 3000 rpm! Good lord, my wife (who is 64) drives her Toyota Highlander harder than that--put her in the Mustang and she's the "little old lady from Pasedena"...

It is true that V8s have more torque at lower rpms, however that doesn't mean it's producing that torque efficiently a few hundred rpm over idle.

If you are cruising at a steady speed on relatively level ground you can downshift and let the engine run at lower revs, however you may find that you have to give it more throttle at the lower engine speed than at higher rpms. When that happens the lower gear (less throttle/higher engine speed) will be the more efficient gear.

"Very short...trips" will kill your fuel economy. Not only are you not getting out of the lower gears, until the engine is up to normal operating temperature it will run rich.

Reducing weight will help, however with your routine driving you would have to be lose 500+ lbs to make any noticeable difference.

The 13 mpg you reported is a bit lower than I'd expect for your driving, however stop granny shifting and that will go up a couple mpg. If fuel economy is a major concern then you have the wrong vehicle.

One last issue, you are not doing that engine any favour driving it as you do. Take that puppy and wind it out once a week, and take it up on the highway for a 40-50 mile trip after that. It will run better and last longer if you blow out the crap and let in run up to full operating temperature once in a while.

Thanks for the replies and thanks Cliffyk. You guys have been really helpful. Well I just went on another drive (driving at 3am in Santa Monica where there is practically no traffic is just great) and I tried shifting at 2500rpm's instead and I can feel that it is in fact so much better. It doesn't lack power anymore for a few seconds like it did when I shifted at 2k.

So 3000rpm's is really the way to go huh? As long as it is doing me better than shifting at 2k then I am fine with it. I just keep thinking to myself that I am working the engine harder than it has to because it just sounds so loud....Maybe I need to get into my head that V8's are just louder than 4cyl's lol.


So if I am at an odd constant speed for a short while where I am like in 3rd gear at like 2000-2500rpm's thats completely fine?


I guess I am just too worried about babying my car, but if staying at higher rpm's is better than by all means I will do it...

Gas mileage isn't a major concern for me but I was really expecting to be getting better than 13-14mpg. By granny shifting do you just mean shifting too slowly?



Brandon

I used to get 27-28 on highway and 17-19 around town and I never shifted at 3,000 RPM's unless I was taking off fast. Look in the service manual, it tells you when to shift for optimal fuel economy. As I recall, mine told me to shift at 14 MPH, 25 MPH, 35 MPH, and then at 45 MPH.

I was getting 13-14 mpg average when I first started keeping track of it, most of my driving was to and from work which is about 10 miles away and what I did was to try using different routs to get there and taking a way that is less direct but has less traffic and less stoplights got me up to 16-18 mpg. Also for a week I was going in early and staying late and missed all the traffic which got me to 20 mpg.

In the last two weeks I have driven ~50 miles on campus only 20mph speed limit and tons of stop an and go I was getting around 12mpg.

But back at home doing 5 mile commutes max, at around 50 I get like 14-16mpg.