Odometer Roll Back
 

It sounds illegal, but for purposes of entertainment only, does anyone do this or know how?
I am writing a research paper on it...
If you would like, you can send me a private message...
thanks in advance.

lol... *COUGH*....*COUGH*

FUGGETTABOUTIT !!!

We're no longer in the days of mechanical odometers.

:surrender

That's not what I hear. I heard people have installed toggle switches to turn them on and off whenever they want.... Sounds alot easier than taking the dash apart.

The only thing that could work is pulling the fuse for the odometer, but that will probably disable other things as well.

No that wont work. OBD-II also stores odometer readings in the PCM itself. Even if you physically removed the odometer, the PCM will still accumulate mileage. It is also stored in non-volitile memory, so even if you disconnect the battery, it will not be lost.

Ah. Damn ODB-2. It worked on some older cars I owned with digital odometers.

Drive around in reverse gear and you can roll back odometer.

:pofl:

Don't laugh; that actually worked on my 1990 CRX.

buying a new car is a great way to roll back the odometer

Did you watch "Ferris Bueller's Day Off"?

Swapping out the odometers worked in the 2nd Gen, at least according to posts put on here.. So it's not really a OBD-II thing, as just more technology added to the system. And this is a good thing.

The scene where the Ferrari went out the window always brings a tear to my eye. :rofl:

That will give the appearence of rolling it back, but the OBD-II still stores the mileage. Plus, rolling back the milage only works to an extent before it becomes obvious what was done.

It's very easy to change the odometer, just plug a computer and change the numbers. It's easier than the older ones because there's no clear marks of opening or fingerprints.


I heard it's easy it cost about 600 US dollars for the job. Here in Canada a study reveals that a lot of used cars don't have the good mileage.

http://www.guideauto.com/AlbumPhoto/lecure278532711.jpg

Yes. Great scene. BUT it does actually work on some cars is all I'm saying. :D

I didn't know it actually works on some cars.
I wonder how many cars on the road today that can roll back the odometer like this.

>>That will give the appearence of rolling it back, but the OBD-II still stores the mileage. Plus, rolling back the milage only works to an extent before it becomes obvious what was done.<<

There was a huge debate on this a couple of years ago in regards to the 2gen, and it turns out that no, the OBD-II doesn't store the long term mileage, at least not in the 2gen. OBD-II is a standard that each car doesn't fully utilize the full feature set. Plenty of OBD-II cars our there without digital odometers. The hack in the 2nd Gen was to put in a alternate instrument cluster in the car. And then swap it back. When you swap back the original, it would get an error code on the OBD-II, but a reset of the OBD-II would clear out the error code from the OBD-II. The OBD-II in the 2nd gen does not store mileage.

ok, lets clear a few things up...

Every car DOES implement the full feature set of OBD-2. It is required by federal law in order to sell a vehicle in this country. You are probably thinking that not every car publishes their full feature set, over the OBD diagnostic port. That part, is true. Typically the japanese companies have been publishing the bare minimum that is required. However, things are starting to change. They are starting to publish everything, the tools vendors just need to invest some time/effort in being able to decode their "proprietary" APIs. But with the advent of CAN (Car area network), which is going to be federally mandated in a few years, things are going to get standardized and easier to do.

Yes, there are plenty of non digital odometer cars. My Pontiac GTP is one of them. However, the PCM still stores mileage independently of the mechanical odometer. Digital odometers are the same way. Some digital odometers accrue mileage independently of the PCM, some just read the mileage from the PCM. But all PCMs after 96' will store the mileage.

Honda would not be stupid to not implement a required OBD feature. They already tried that back when the last gen accord came out. They disabled the fuel vapor recovery warning system, because of some bugs. They got fined by the federal government something like half a billion dollars. The fine was reduced, and Honda fixed the OBD compliance issue. (I'm not singling out Honda, Toyota did something similar). Anyways, I'm sure Honda will not want to repeat that.

Also, FWIW, just because a speedo/odometer/etc, is analog looking, doesn't mean it mechanical in operation. The speedo in my Pontiac is analog looking, but it doesn't operate via a cable like a traditional analog speedo. It operates on a digital signal from the PCM. How do you think some manufacturers get all the gauages to salute you at their maximum positions on startup :tongue:

Also FWIW, assuming the "driving the car in reverse" trick would work, all one would need is an o-scope and signal generator. You'd have to tap into the speedo wire to see the signal pattern that is being generated while driving in reverse and then replicate the signal pattern using the signal generator (and probably some black box components). You'd then be able to inject the "reverse" speedo signal into the instrument cluster without even putting the car in gear. I've never tried it but would think it would be a viable (yet expensive) solution.

BTW...I spliced a switch into my '93 saturn that had a mechanical odo but driven by an electrical impulse.

avs007 is accurate. There is no "easy" way around the odometer recordings. Complete replacement of certain parts at thousands of dollars along witht he federally required paperwork would make any such attempt by the 16 year olds on this thread un-realistic. So, if you were truly writing a paper on it, then you need to do it the right way. PM avs007 and he can probably even point you to the websites that outline the legal details. In short, nope you can't simply place a "toggle" switch in the system. It won't work.

Well I guess the experts have changed there minds since a couple of years ago! Well I don't want to spread misinformation, and I my knowledge of OBD-II only comes from hooking up and reading off the data, and just some casual reading. So I stand corrected. :thumbsup:

So if the OBD-II is recording all this, then it is still pretty simple. Swap out the PCM computer, the OBD-II computer and the Instrument Cluster.

Now of course I imagine you won't be able to start your car, as your key won't be recognized by the swapped computer. Or you could put 44" Wagon wheels on your car. So every mile you drove , would only appear as 1/2 a mile on the ODO.

I think back in the 80's some people unhooked the odo cable from the tranny, or on more modern units put a huge ass electric magnet on the sensor screwing it's ability to detect speed properly.


But needless to say, as impossible as it seems. It is still unfortunately being done. The system is not fool proof.

I wouldn't say the parts are $1,000's of dollars, that stuff shows up on ebay all the time.

Yea I heard they can hook up an electronic device to change the odomoters that are digitally shown.

Or..you can always try Matilda's dad's technique and drive backward in circles. haha

I think that's what he did..

Back in the "really good old days" you could decouple the speedo cable from the tranny, attach an electric drill to the cable, and run the speedo/odometer in reverse to remove miles. That was the method of choice when I was a kid.

I did a bit of searching, I think the original 2gen question got locked down, and deleted, because I think it was hitting to close to the truth!

Somebody here remember that thread? Some guy had a friend at the Acura Dealership, they were doing some work on his dash, and his friend just gave him
another instrument cluster to use for a few days. And then swapped the original
back in. Now I argued profusely with the guy as well did a lot of others, but he did come up with a lot of pictures, and in the end, it looked like he was telling the truth. And the Acura mechanic said you couldn't tell any difference.

I posted in that thread, which was around early 2002. I'm sure some old timers around here may remember that thread. It got pretty HEATED, and got pretty large.. But I think it ended up to everybodies dismay that the part that was keeping the mileage in memory was actually in the instrument cluster.

I found one weak thread that sort of seems to expose a little light on it.


https://acurazine.com/forums/showthr...t+cluster+swap

Mileage stored elsewhere...
 

That raises a related question.

There was a thread here where an owner got his odometer wiped by the dealer when they were attempting to diagnose and fix the flatline OAT problem.

This owner spent months wrangling with the dealer, Acura, and the state of CA over this and finally ended up having the odometer reprogrammed with an approximate mileage. If the actual mileage is being stored in second place on the vehicle, why couldn't the true mileage have been read from there and re-programmed into the new odometer?

An interesting contradiction, no?

Sounds like a good job for "Mythbusters".

Research paper?

Sounds like the same excuse Pete Townsend is using for browsing kiddy porn sites on the internet.

Okay while cars are required to have the core OBD-II feature set which is all air quality control related. That's why we have OBD-II and OBD in the first place. Mileage of the car is not one of the core features required. That is something that is added in as a proprietary feature set for each car maker that just so happens to utilize the OBD-II data interface. It makes sense, go ahead and use the existing data port in the car rather than creating another one.

So your argument simply doesn't apply. As mileage is not a OBD-II requirement. Feel free to prove me otherwise.

Proprietary Sensor Readings

Though not part of the EPA's OBD II standard, the diagnostic read-outs used by dealership technicians are also read through the OBD II connector. These service codes show you such things as knock sensor operation, FI pulse width, ignition voltage, individual cylinder misfires, transmission shift points and ABS brake condition. There can be over 300 readings available, depending on the vehicle manufacturer and model. Vehicles vary in the readings they will support. Scanners vary widely in the number of these signals that they can read. Some show just the basic OBD or OBD II signals, others show the full range of service codes.

Now when it came to 2Gen as had been hashed out here before the thread got locked up, It went something like this: If you disconnect the cluster your transmission will not shift into third gear since the instrument cluster contains the speed signal buffer and controls shift patterns. If its disconnected the PCM shifts gears based on forced shifts at close to RED-LINE do to high transmission line pressure. The PCM does not store mileage although it can be read on a TECH II only if the cluster is plugged in because it reads it from the cluster! There is no easy way to adjust the mileage on the existing cluster.

Now hopefully they fixed this on third Gens, as it ultimately only hurts our resell value if they didn't. And I found it entirely insulting that a Dodge Caravan would have better odometer tampering measures in place than a $30+ Acura.


If you need some background on OBDII
http://www.obdii.com/background.html

I believe Carfax reports include mileage statements from various sources such as yearly inspections, registration/title changes etc. Depending on the state this info may be very scant or really detailed. If you came across a used vehicle that had a mileage reduction over time or a yearly rate of mileage increase that didn't make sense, it would certainly be something to take into consideration.

By 22-inch wheels (not a roll back, but a decreased roll forward). Larger diameter = longer circumference = longer distance per engine revolution = incorrect mileage calculation.

True, and using this theory...if you ran 15" wheels in reverse, you could rollback the odometer MUCH faster. :rofl:

This only works when you back up to the right, as you have to go counter-clockwise, unless you are south of the equator, then you have to go left. :explode:

You're 32 years old and writing a research paper? For what?

Can someone explain me how an odometer works to calculate mileage. Is it a contact near the wheels or something else.


Thanks

It connects to the transmission

In this case just unplug the transmission connection and drive around like that. You'll not have the speedometer and other stuff working, but hey - no mileage is accrued!

Holy ancient thread ressurection, Batman!

If you disconnect the speedometer sensor on the transmission, your CEL will illuminate and VTEC won't engage. I believe on newer Honda/Acura cars, your redline is also reduced to 5500 rpm if the car senses that its drive wheels are not moving.