Odometer and Trip Meter

[Rmay]

Has anyone else noticed this on their car. Every time I put in a tank of gas I reset one of the trip meters to zero. (Just so I can keep track of just how little gas mileage I'm getting.) When I refill I compare the mileage on the trip meter vs. the odometer. They are always different - the trip meter always gives more miles. When the driving is mostly around town, they are fairly close, but when it is mostly (or all) highway, the disparity can be anywhere from 30 to 50 miles.

Anyone know why this is?

[Stoneage_Turbo]

Im gonna try that when i get home ...too bad i will be stuck here for 11 more days ....27 days to go

[maxnix]

Nope, they (the mechanical and the electronic ones) are identical on my 1995 Q45s for each tank or two, then I reset.

[Rmay]

Oops, maybe I wasn't clear. What don't correlate aren't the A and B trip odometers, but the trip odometers (either one) and the main odometer (i.e. on the speedo).

[Q451990]

At each fill-up I write down the miles from the B meter, then reset, and write down the odometer reading. I have to do all of this for tax reasons. In any case... they may be off just a little but in most cases I think it's within 1%. The worst case I see from spot checking is 291 miles on the odometer and 289.5 on the trip meter. Since the mechanical odometer doesn't have a tenths reading, I guess it's within that range...

I do a lot of mixed driving leaning toward the "highway miles" side... I average about 19MPG. If you're seeing a 30-50 mile discrepancy, I'd think there's something wrong.

Heath

[theTony]

Does anyone have a "DTE" (Distance to Empty) feature like I do? I always wonderd how accurate that was. On the same computer it also calculates my average mpg, and it is usually 22-24, mostly around town driving.

[Rmay]

I do a lot of mixed driving leaning toward the "highway miles" side... I average about 19MPG. Heath

You get 19MPG on average? Wow. In a 90Q? When you say "lean" towards highway, I presume you mean something like at 60/40 mix. If I got 15.5 mpg on that kind of mix I would be happy. For my normal driving, which leans (strongly) towards non-highway, I get 12 to 13 mpg.

[Q451990]

To be honest, I was surprised when I calculated it. I live near a lot of semi-highway routes... 45-50 MPH with few stoplights to get to the interstate. That's probably the difference. Last time I checked mileage I was seeing an average of 16-17. It's especially interesting with highs in the upper 90s lately (Q running rich).

Heath

[BradM]

RMay, I've had the same problem since purchasing my Q in the spring of 1999. At every gas fill-up I reset the "A" odometer to zero. I note the mechanical odometer, log it, then figure out the gas mileage. The mechanical odometer MOST always lags the digital trip odometer ("A"). Sometimes the lag is up to 20%! Most often it is around a 5 mile difference when I fill-up after 200-300 miles. I have actually noticed the mechanical odometer stop turning before too! I brought this up on the old Yahoo! board and never got an answer. Methinks my 1990 Q45 at 205,000 miles really has about 220,000 miles on it. Good news is my new transmission 12 mos/12k mile warranty will last a little longer!

Brad1990 Q Pearl White with 204,000 miles (or more)

[aaacomp]

Isn't one in Kilometers on the Q:D

[greg_atlanta]

Odometers can break. Yours is just breaking slowly. Think of it as a fountain of youth.... or added value if you sell the car!

My odometer read 131,000 when I bought my '92 Q, now it reads about 138,000. Have driven at least 45,000 miles during that timeframe (manually tracked though B trip odometer reset once per month).

My odometer gets stuck in certain places, sometimes for weeks at a time. Then moves a little, then gets stuck......

Not worth fixing.

[greg_atlanta]

On the mileage note... I used to ALWAYS get 15 mpg running around town. Lately I've been getting 17 mpg. Of course no A/C!

:firehead

(really not that bad... except when it rains. you get used to it.)

[BradM]

aaacomp said: "Isn't one in Kilometers on the Q?"

BradM replies: The Q45 (at least my yr - 1990) has a manual odometer (included in the speedometer gauge) like all cars. Additionally, it has an "A" and a "B" trip odometer display. This display is digital and is in a multi-function screen located in the lower left side of the main instrument panel. When all doors are fully closed and engine is running, the mileage on the "A" and "B" will be displayed. If you have a malfunction such as "brake pads worn" or "low fuel" among MANY others, the trip mileages will NOT be displayed as the continual display of the malfunction takes precedence. Either "A" or "B" can be reset to zero (00.0) by twisting the knob clockwise or counter-clockwise. By pushing in this knob with the mileage being displayed, both "A" and "B" will convert from miles to kilometers or vice versa.

Sorry for the lengthy answer. Among other things a nice feature that a technical person like me appreciates in a luxury auto.

BradM

[DenverQ]

Mine has never said Low fuel in the 2 years I have owned it i wonder what could be wrong

[Q45tech]

The Q hold 22.5 gallons.The low fuel warning activates when around 2.5-3.0 gallons remain. Empty on the needle [on mine] means 17.5-18.0 gallons have been used ---- [5.0-4.5 remain].Back when I first purchased the Q [and didn't understand fuel pumps], I tested the system drove 48 miles after the low fuel light came on, it took 21.6 gallons to start flowing out the filler neck.Now I always refill when 15-17 have been used except on interstates when 3 hours is all I can stand.

Everyone will be slightly different and some very different especially if a fuel pump change bent the float arm or relocated the light sensor even 1/16" [as the bottom of the tank is large in area!

After 237k and good gasoline records my Q has averaged 19.67 mpg......very few sustained hours above 80 mph but half its life was at 70-75 mph where 22-23 mpg is the norm but 99% of the gasoline was non oxygenated [GA, FL, NC, SC, TN].Oxygenated seems to be 1-1.5 mpg worse even though the EPA says it should only be half that amount?

The bulk of the last 150k was on QT marketed fuel.

[reggiegsd]

I've seen some funny milage numbers quoted in some of these threads. 15 and 16 mpg. I've never gotten less than 19 mpg and that was charging hard through the mountains of WV, VA, and NC. With the AC on.

With the cruise control on 75 and no AC, I can bank on 23.5 to 24 mpg. Mixed driving around town is 20 to 21 MPG. Four and a half hours with the cruise on 85 got me 21.5 mpg.

To me, 16 mpg means something is wrong. (O2 sensors?)

[BradM]

The low fuel sensor is attached to the bottom of the fuel sending unit. It (sending unit)also has the fuel pump attached to it as well. According to the dealer, the low fuel sensor is NOT sold seperately but WITH the fuel sending unit. I forget the price, but I didn't see the need to spend the extra $$ for a redundant system. My fuel sending unit works great, plus I'm always re-filling by 300 miles anyway.

My manual (1990 Q) outlines tests to check if the low fuel sensor works. I'm almost positive it needs to be removed from the tank though.

I know you're curious if it works, but there are some lights and warnings I NEVER want to see.

Brad

[natsoundup]

I always have a tight range when I am on the road.... 20.3-20.5...

I guess in mixed use it's around 15-16... I drive more around town than on the road...

But I have never hit the 21 mpg mark...

[DenverQ]

I average about 19 myself and thats 50/50

I have never ever seen that low fuel light even when I ran it out of gas when the fuel pump went out. DOH!

[reggiegsd]

Wow.

I guess I need to ammend my post above. I've just spent two weeks in Tampa, FL. This is the first time I have driven the Q in consistent high heat (95 or so). My milage has fallen to about 17 mpg and NO POWER.

The car goes back North this weekend. I'm sure it will be much happier.