Have any of you checked the accuracy of the avg mileage figure on the overhead console against avg mileage based on miles driven and fuel consumed? I didn't bother to check mine before we put a chip in the truck, and now the console figure is consistently off by several miles per gallon. I'm wondering how the computer figures the avg mileage, and if there is anyway to improve it's accuracy.

Thanks:-)

Beth
02 PSD Excursion
97 F150
93 Honda Prelude VTEC
93 Mazda TT Rx7 R1
01 Corvette Z06

 

The computer uses a few different inputs.

First one is the speedometer/Odometer.
The second is the PCM. It counts injector pulses, knows fuel metered and then calculates out fuel usage used based on throttle position & distance. As for recalibrating, I don't know. Maybe a dealer a do it?

 

Hmm...interesting. Not really sure I want to take it to the dealer with the computer reprogrammed, and ask them to recalibrate it.
Has anyone else noticed this difference with a chip? (I have the Superchip programmer with two available stages)
Thanks for your help:-)

Beth
02 PSD Excursion
97 F150
93 Honda Prelude VTEC
93 Mazda TT Rx7 R1
01 Corvette Z06

 

Beth,

why don't you post your question down in the CHIP forum? Ken (webmaster) reads those posts more frequently. He may be able to solve your dilemma. He sells the diablo chips here on the online store. Did you get yours here?

 

Good idea, I'll try that. Thanks:-) Yes, I did buy it from Ken, and I got a great deal!:-)

Thanks again.

Beth
02 PSD Excursion
97 F150
93 Honda Prelude VTEC
93 Mazda TT Rx7 R1
01 Corvette Z06

 

Hello again, just thought I would add my $0.02 to this string regarding MPG and the on-board information center. So far in my experience the on-board MPG computer is not worth it's weight in plastic. It's never as accurate as figuring out your own mileage and it needs to be re-calibrated often according to to a Ford mechanic. He said to re-calibrate the on-board information center just hold down both buttons for about two minutes and you will see the display changing as it goes through the calibration. BUT, it hasn't worked for me yet.

On a similar note I have been tracking my MPG on every tank fill since I purchased my 2000 Excursion V10 and the mileage has steadily decreased. I'm currently at 11 MPG although the vehicle has 51K miles and seems to run great.

Has anyone experienced the same issue and could it be fixed?

Oh, one other thing, where is the PCV valve on a 2000 Excursion V10? I have looked every ware and the shop manual doesn't help.

 

>
>On a similar note I have been tracking my MPG on every tank
>fill since I purchased my 2000 Excursion V10 and the mileage
>has steadily decreased. I'm currently at 11 MPG although
>the vehicle has 51K miles and seems to run great.
>
Basically I agree, I have a 2k Ex 4x4 V10. I have noticed a descrepancy in the overhead reading. Last tank I read 11.0 mpg on the overhead, this was reset at fill-up. Actual was 10.194 mpg calculated from fill-up to fill-up and mileage from trip odometer. I am partially through a tank with the Tornado Air installed, the overhead reads a higher fuel effeciency. I will post my results in the "Tornado" string later this week.

Scott

 

I need to correct my last posting regarding the function of the on-board information center. Apparently I was wrong about the method to re-calibrate the MPG display. To reset the display make sure the MPG settings is displayed and just push both buttons at the same time quickly to zero out the reading. Then drive around until the display seems to remain constant because it updates about every minute.

While I was watching the MPG reading climb on my drive home via the highway it dawned on me why the computer 's MPG reading is different from my calculated MPG figure. The on-board information center calculates a new MPG every few minutes giving you an instantaneous MPG reading where as my MPG calculation after each fill up is actually the average MPG. My daily driving routine is about 80% highway and 20% city so it makes since that the instantaneous MPG reading would be higher then the average MPG figure.

So, I guess the on-board MPG read out is more accurate then I thought as long as you reset it after each fill up. Currently my average MPG=11.1 but my instantaneous MPG=12.7 (Highway).

 

>>The on-board information center calculates a new MPG every few
>minutes giving you an instantaneous MPG reading where as my
>MPG calculation after each fill up is actually the average
>MPG. My daily driving routine is about 80% highway and 20%
>city so it makes since that the instantaneous MPG reading
>would be higher then the average MPG figure.

I believe it does indeed average it over the tankful (so long as you don't reset it) and does not show you instantaneous mileage. It will however, give you instantaneous MPG for the first reading or so after you reset it. Then it averages each reading with all the others. If I don't reset it for the tankful (hard to do, I like seeing those high numbers) it will reflect the accurate, average mileage +/- a few tenths.

Funny, my Excursion seems to not have some of the quirks that others do. No flutter (orginal Y-pipe), functional & accurate MPG gauge etc.

 

I'm going to try to find out the true function of the MPG computer from one of my contacts and report back. If in deed it is designed to display avg. mpg then my unit is way off because my calculated mpg is much lower.

 

Hello all,
In an effort not to repeat all that I have written, please see my postings in the "tornado" string. I have actual averages vs. on board computer readings. I do agree with Monsta, the on board computer does slow down on changes as time/mileage increases, therefore completing average computations.

Love my Ex,
Scott

 

Yes, it seems that the on board information center does calculate average mpg. My Ford contact informs me that the Average Fuel Economy (AFE) display was designed to give customers an average mpg for a road trip or just the avg. mpg from tank full to tank full. There is no need to reset the AFE unless you want a fresh reading for a given distance like a road trip. If the customer never resets the AFE the reading will be a continuous average from the initial reset.

Although, I still could not get an actual value for the accuracy of the AFE read out.

 

 

OK, if anyone is still following this string I have some new information to add. About a tank and half ago I dropped off my 2000 Excursion V10 4x4 for service at my local Ford dealer. I bought the vehicle used so I opted for the ESP which has now paid it self off. I waited until I had several issues for the dealer to address like:

- Front end wonder (there is a TSB to replace the front ball joints)
- Rear axle pinion seal leak (second fix)
- Broken head light switch
- Poor fuel economy (10 mpg and falling)
- Replace PCV valve
- Front hubs too stiff to turn by hand

So, the dealer fixed everything and it only cost me the $100 deductible. The best news is they re-flashed the PCM with the latest calibration available to address the poor fuel economy and I jumped from 10 mpg to 12 mpg instantly which I just confirmed on the last full tank. Although the Average Fuel Economy (AFE) display is still off it's only off by a 0.5mpg. I bet I could get 12.5 mpg on a long road trip, which sounds good to me considering my vehicle weighs 7,600 Lbs with only a full tank of gas and a 4.10 gear. I weighed my Excursion on a certified Truck Scale just the other day.

The PSD Excursion must weigh about 8K Lbs. Wow!
:-staun

 

I just bougth a 2001 V10 Excursion used and am interested in an ESP. How do you go about doing that. It is at 27,000 miles so I have a little time, but I want continuous warranty coverage. Is there a price range I should expect? Think I'll have any trouble having the K&N intake? It was there when I got it. Thanks in advance.

Jim