TUNE DOESN'T LAST

[F111]

We had a Predator 7130 thrown in when we bought a used 2004 Dodge Diesel pickup, the 24V Cummins.

When we put a mileage/performance tune in it, mileage around town shoots up to 19 mpg around town. Shut truck off, start in the morning, even if we restart the average fuel trip consumption thing, it still plummets RIGHT back down to 15 or so mpg.

Why does the tune not last?

We have used actual miles calculated with actual gallons for the baseline figure, and it matched the trip computer almost exactly.

Why does this thing not work for more than one day at a time?

Do we need to re-re-re-reload the program every time we shut the truck off?

Because every time we load the mileage/performance program, we get instant increase to 19 mpg. Then every time, next day, back down to 15 mpg even if we reset the trip computer thing.

Fuel filters are new, and this is pathetic.

If it is oxygen sensors, why do they work immediately after installing the tune, then suddenly go bad when you park the truck overnight?

We are using Amsoil synthetic with bypass filtration system, just changed. New fuel filters, external fuel pump, since the in-tank went bad. It did everything it is doing absolutely exactly the same before we changed the pump.

Are there other, mystery fuel filters installed that we didn't change? That get clogged after one day, but only if a Diablosport tune is installed?

I need to know every single possible thing to check.

Or, is the Diablosport thing punishing us because someone ELSE stole a tune off it before selling us the truck, so it goes into weak cripple mode, dying after one day?

Or are these designed to fail after a few years and force you to buy a new one, like cellular phones are reputed to be?

I dunno. But it IS happening, and it IS weird.

[concoursd]

what are you talking about? Diesel engines dont have oxygen sensors.

Someone else stole a tune off of it....????
If the predator installs a performance tune successfully, then it is tuned. End of story. You can check by going to options and then click on show last tune written. If it says diablo tune or something like that then you have it tuned. If it says factory tune, then you have a stock file in there.

Fuel mileage will vary based on driving conditions. Your fuel mileage readout should be way off with a performance tune installed. OEM fuel economy estimator does not calibrate itself to the diablosport tune settings and therefore will always be off.

What software revision are you running in the U7130? it is located at the top of the main menu screen.

What dodge calibration does your truck have? Go to diagnostics and go to show CALID.

If you have a defective Predator, it usually will not function. You stated that it is installing and uninstalling a performance tune...so no it is not like a cell phone that is designed to fail and it is doubtful that it has failed. The Predator is a piece of hardware that connects to your truck and delivers a piece of software. If vehicle programming is unsuccessful, then the tuning process will display an error and the vehicle performance will not be changed.

With the performacne tune installed, if you get on the gas hard, you should definitely feel an increase in power and see some black smoke come out of the tailpipe. That will also verify that the correct tune was installed, besides the aforementioned show last tune written method.

[mikel]

Well, bottom line here...once the tune is flashed to the PCM it is there.
If thew tune went away, the truck would not run, as the PCM would be blank...it cannot just go back to stock....

[F111]

Okay. Great, then. But why does the thing show 19 mpg for the first day, then even if you reset the mileage thing later on the same tune, it shows 15 mpg on the second day?

I dont have the thing to update to the latest tune. Trying to convince the owner it would be worthwhile to spend the 32 bucks.

The good news, research-wise, is that we are going on a trip, hauling a 10,000 pound or so trailer to another state, and will be able to see what kinda of mileage we get on the trip. I am going to lobby for stock tune for first tank, then perf/mpg or two tune for next tank, since the driving conditions will be close to identical.

Which tune will yield better mileage with a heavy trailer? tow or mpg/performance? We aren't planning on breaking any records for speed, just want the most efficient means of getting us and the trailer up to where we are going.

[mikel]

Dont put any faith in that DIC readout.
It is likely not even right with the stock tune.
Have you buddy hand calculate the mileage for accurate results....

Thanks

[concoursd]

if you are towing over 8,000 lbs then I recommnend sticking with the tow setting. The tow setting is designed for towing loads up to Dodge's stated weight limits. The higer settings will probably cause too much strain on the drivetrain and may overheat the turbo.

As stated before, you will not always get the same mileage on every day as not every day is the same... The fuel economy will vary based on driving conditions and driver. As mentioned before, stop using the mileage indicator. It is false. Your best method of testing would be to test towing 10,000 lb. load with the stock tune with the same driver/driving style. If you hit traffic on your trip consider that loss in mileage as traffic equals zero mpg. Then tow the same load with the tow setting under the same driver and conditions. Be sure to fill up in between trips and once again at the end of the trip and HAND calculate the mileage. That way you get a REAL test on fuel economy.

[F111]

Okay. I think we will use the normal one, then after a distance, refill, use a tune, and hand calculate.