Low MPG?

Teeson, what kind of CAI do you have? You described your driving habits as I would describe mine (except for maybe watching the RPMs as closely, but I do have a lead foot for sure)... So if you're getting good numbers, I should try some mods you've

Lol I defs have a solid lead foot, but I still average 550-600km a tank. Shifting at 3 is just a habit now, may not be 3 exactly everytime..
I have a k&n typhoon that I got off a member here a while back.. But I don't think it's all that necessary, a drop in k&n filter should give you 90% of the gains a CAI +hydro bag would.
 
Wait, so because I drove 5mph over the posted speed limit and not 80mph my experiences are not normal? Right.

Bottom line is mpg is all how you drive it.

Yep, if I drive mine 75-80 it'll burn a very small amt of oil ( less than 1/8 qt a month) and the mpg will drop down to 24-25 mpg. As long as I do normal 3000-3500 rpm shifts in manual mode or just drive normal in auto mode and stay between 65-70 for the most part, it will do 30-31 mpg and not burn any oil.

Digital,

That's not at all what I said...however, the difference in MPG with just a 10mph variation is pretty big, as you can see from this other guy's post...also, check out Aerocivic dot com...10mph difference even on an ecomodded car means a difference of 10 MPG.

Aside from the difference in speed, which clearly makes a difference - your car is not stock. Those two variables account for your mileage. It's not rocket science. If you had the stock airbox and OEM paper filter, stock exhaust, etc and drove a little faster to match my speed - your mileage would be the same as mine.

Not sure where you got "your experiences are abnormal" from. They are perfectly normal - for a guy who drives his car slow and has airflow modifications. It's *partly* how you drive it. The other part is what's done to it modification wise. Intake and exhaust make a substantial increase to economy.
 
Just FYI I don't have any airbox mods (or any real performance mods). My ram hood isn't set up to feed the airbox yet so if anything it would be dropping the mpg.
 
Teeson, what kind of CAI do you have? You described your driving habits as I would describe mine (except for maybe watching the RPMs as closely, but I do have a lead foot for sure)... So if you're getting good numbers, I should try some mods you've

Lol I defs have a solid lead foot, but I still average 550-600km a tank. Shifting at 3 is just a habit now, may not be 3 exactly everytime..
I have a k&n typhoon that I got off a member here a while back.. But I don't think it's all that necessary, a drop in k&n filter should give you 90% of the gains a CAI +hydro bag would.
I might try the K&N, but I'd love to have a CAI, just because I love to upgrade on performance when I can. Plus, they look good, and sound good too. I can't do anything "too easy" either. I have an incessant need to tinker. ;)
 
I get at least 30 MPG highway with the kl v6 with a LSD 28 city/highway IIRC I get around 400 miles before my gas light comes on with 3-4 gallons left, closer to 4 and our tanks are 16.5?? So 12.5 gallons for 400 miles is 32 mpg and low end 400 miles with 14 gallons is 28.5 mpg plus my timing is a little off and my car runs rich

That's without a/c
 
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I get at least 30 MPG highway with the kl v6 with a LSD 28 city/highway IIRC I get around 400 miles before my gas light comes on with 3-4 gallons left, closer to 4 and our tanks are 16.5?? So 12.5 gallons for 400 miles is 32 mpg and low end 400 miles with 14 gallons is 28.5 mpg plus my timing is a little off and my car runs rich

That's without a/c

I've heard of people getting those kinds of numbers before, which is why I've been thinking there's got to be something else I can mod to achieve the better economy. But it had to be an almost guaranteed gain - I drive across town on a daily basis, and I'm a single parent. I love to play around with performance parts, and working to get MPG gains, but don't have big bucks to throw into car funds currently.
 
I gotta wonder how people do their calculations sometimes.

On Fuelly, here's what the average numbers look like.

For 2002 models, there are 101 cars tracked, totaling nearly 1 million miles. The average MPG of those 101 combined '02 P5's is 26.1 MPG.

For the '03's, there are 67 cars tracked with just under 700,000 miles. Average MPG for those is 26.5 MPG.

So, when people claim to get over 32 MPG, it really does seem like an anomaly...unless they have 100% freeway commutes all the time and have some modifications (filter, exhaust, etc). But for mixed driving? I dunno.



I've heard of people getting those kinds of numbers before, which is why I've been thinking there's got to be something else I can mod to achieve the better economy. But it had to be an almost guaranteed gain - I drive across town on a daily basis, and I'm a single parent. I love to play around with performance parts, and working to get MPG gains, but don't have big bucks to throw into car funds currently.

K&N in the airbox ($40) and an exhaust ($120-180) are a start. If your car is in a good state of tune, and your tire pressure is near the max, then driving style really makes one of the most significant differences in MPG. Grille guards do quite a bit, but I don't know if that's a good idea in KY in the summer. Lowering springs ($210 ish) and some flat panels for the bottom of the car would also help a bit.

Check out ecomodder.com and aerocivic.com for some other ideas.
 
Different gas pumps shut off at different fill levels, messing up calculations. To over ride that variable, I fill to the top of the fill tube, visually see fuel.

5-speed, stock 03 P5 w/ 03 motor, new plugs and air cleaner, tires at 40 psi, summer time, strictly freeway, once got 39 mpg, several times got 37 mpg, generally 35. W/ 02 replacement motor,, have never gotten better than 34, mostly closer to 30.
 
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Different gas pumps shut off at different fill levels, messing up calculations. To over ride that variable, I fill to the top of the fill tube, visually see fuel.

5-speed, stock 03 P5 w/ 03 motor, new plugs and air vleaner, tires at 40 psi, summer time, strickly freeway, once got 39 mpg, several times got 37 mpg, generally 35. W/ 02 replacement motor,, have never gotten better than 34, mostly closer to 30.

That's the issue I run in to...pumps stopping at different levels. I thought about topping off, but thought that was bad? I got 32 MPG on my last tank with 100% city driving. But I have a feeling this current tank will be lower due to different fill level of the pump. But I figure it all evens out in the end no? I'm averaging 30.6 MPG per my Fuelly account.
 
I've been filling to top for 200 k and no problems yet.
Also, 10 miles later it's not topped off any longer from gas use.
Plus, I get accurate calculations each time.
Too much bother for me, otherwise.
Only variable now is if gas station pump is inaccurate.
 
Howdy there, just thought I'd pop in to point out the potential these cars have for daily driving.

I average between 45-50 mpg on highway, 35-40 city, depending on how I rev it.

After my next set of mods, I expect another 5 mpg easily.

Remove your cat (if possible) it helps quite a bit. Remove your racks and plug the rail holes, thats easily another 2-3 free mpg.
I was able to get an increase on my headers along with the no cat exhaust from corksport. About another 2-3 as well.

I built an upper grillblock from ABS plastic and blocked the entire upper grill. I live in the NW and the temps don't even rise AT ALL with it blocked. But even a partial will help if your somewhere hot.

I have done numerous mods to the car but just these few simple ones will easily give you at least 7-8 for "free" No driving changes required.

Cheers!
 
Remove your racks and plug the rail holes, thats easily another 2-3 free mpg.
Are you talking about removing the cross bars and the rails? Should be able to get most or all of that just by removing the cross bars and putting the filler caps on. I'll be checkin this out soon. Might even go for some filler strips if I make no racks a more permanent thing. Don't really care for how it looks with just the capped rails left on it too much. Would rather take the rails off completely and go with the filler strips if leaving it that way.
 
Are you talking about removing the cross bars and the rails? Should be able to get most or all of that just by removing the cross bars and putting the filler caps on. I'll be checkin this out soon. Might even go for some filler strips if I make no racks a more permanent thing. Don't really care for how it looks with just the capped rails left on it too much. Would rather take the rails off completely and go with the filler strips if leaving it that way.

I did some minor testing with string dyno, coastdown runs and a camera car watching.

I removed my racks, all parts of them. Left the idk what you call them, the gaps? Tested it for a few runs to get a stable baseline.

Later I put in some cardboard "filler strips" to try and test it as well.

Then it rained on me and it ruined my test strips so I ordered the real things (loser)
 
Is it possible that it takes a couple of tanks of gas for the fuel system to adjust? Since I had the service done a few weeks ago, I've gone from about 25mpg to 27mpg. The last 2 tanks have been at 27mpg.
I haven't really changed my driving habits at all. I do recall ONE DAY that I tried to keep the RPMs at 3k or less. But since I'm always in a hurry to get to work and home in the afternoon, my lead foot takes over. Lol
What about that age old question.... Better economy with windows down or windows up and AC running? Who has tested this one?
 
What about that age old question.... Better economy with windows down or windows up and AC running? Who has tested this one?

mythbusters. :D

try unplugging your battery for a couple minutes to reset the ECU (and unfortunately your radio) this causes the ECU to relearn it's environment a little, and is often included in the instructions of CAI etc.
 
Is it possible that it takes a couple of tanks of gas for the fuel system to adjust? Since I had the service done a few weeks ago, I've gone from about 25mpg to 27mpg. The last 2 tanks have been at 27mpg.
I haven't really changed my driving habits at all. I do recall ONE DAY that I tried to keep the RPMs at 3k or less. But since I'm always in a hurry to get to work and home in the afternoon, my lead foot takes over. Lol
What about that age old question.... Better economy with windows down or windows up and AC running? Who has tested this one?

Windows down is better until speeds reach 70 mph or greater. Then AC is more eco. Basically...unless your a speeder...windows down will always be more friendly on your mileage.

Source: Hypermiling forum test's. Don't have the links handy, but that is the results of several such tests. Sure you could find them easily with a quick google.

(I also happen to know someone who fitted "window skirts" to deflect air to the outside of the car while his windows were open. He had several instant MPG tools installed in his vehicle and their was no noticeable decrease of mileage versus closed window.)
 
try unplugging your battery for a couple minutes to reset the ECU (and unfortunately your radio) this causes the ECU to relearn it's environment a little, and is often included in the instructions of CAI etc.
Why, when all I'm using to run my mileage numbers is the gas pumps, the odometer, and my phone app? I always fill the tank just to the auto shutoff, and use that number of gallons to fill up with the number of miles on the trip odometer. I wouldn't have thought that anything else would make a difference. Unless you're saying that would actually improve my economy??
 

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