greasemonki

Well, after watching my fuel mileage continue to decline over the past few months, I took the 45 minutes it takes and reset the APPS. all I can saw is wOOt!!! Fuel mileage is back up through the roof! I blamed my poor fuel mileage on a combination of winter blend fuel and the new USLD, and my right foot, but to my relief, I can fuel up smiling, knowing I'm back to the high teens/ low 20s for mileage. So a suggestion for some with fuel mileage pains. Try the APPS reset, it might just work wonders.


<My apologies to the mods if this belongs in the "other" forum>

Mountaineer

I did the same thing . My best milage ever was obtained after the apps reset.

the496rocket

could you post the instructions for apps reset? my milage also seems terrible

dieselfan

https://www.dieseltruckresource.com/...n&onlynewfaq=1
__________________

heres the instructions.

dieselfan

tool

That is not the right instructions...... You need a voltmeter and you need to manually set the voltage on the APPS.

Try the TST website.

Baggy

Can you point me to the url? Not sure what the TST site is.

dieselfan

that is the instructions to RESET the apps not change the voltage, there is a difference.

dieselfan

2fun

Anyone know how often this needs to be done???

I only have a bout 350 miles on mine currently, but will keep an eye on things and especially so if this needs to be done at a certain interval...

crobtex

Here is the adjust procedure, it is not the same as the reset:

RESETTING THE APPS SENSOR.
(ACCELERATOR PEDAL POSITION SENSOR)
2ND GENERATION 24 VALVE TRUCKS ONLY.

LIST OF TOOLS NEEDED

DIGITAL VOLT METER
# 20 TORQUE BIT SOCKET
# 1 PHILLIPS
# 10 MM SOCKET

Proper service and repair procedures are vital to ensure personal safety of those performing the repairs. Standard safety procedures and precautions should be followed at all times to eliminate the personal injury or improper service, which could damage the vehicle or compromise its safety.
Although this material has been prepared with the intent to provide reliable information, no liability is assumed in reliance of this material.

It has come to my attention that a lot of people think by disconnecting & re-connecting the batteries and stepping on the throttle it is going to reset the apps, no, that is not correct. It is impossible to adjust your apps if you do not know where it is supposed to be set at. That is why you need the voltmeter.

This is the procedure I use to re-set the apps.

With the key on, engine off you need to probe the apps wire to see where your voltage is currently set at.
The best location to probe the wire is on the PCM (power control module) which is located off the passenger side of the firewall.

· You want the C1 connector, this is the connector closest to the engine,
· You want the orange wire with the dark blue tracer which is pin # 23
· Voltage should read somewhere around 0.5 volts,
· At this point the voltage reading does not matter, it just has to be accurately written down for later reference.

*** TURN THE IGNITION OFF ON THE TRUCK ***




Resetting the APPS Sensor cont. page 2
(Accelerator Pedal Position Sensor)
2nd generation 24 valve trucks only.

· The apps sensor is located slightly above and a little to the left of the injection pump.

· Remove the black plastic cover that is located by your injection pump.

The two screws that are holding it are plastic, do not put any downward pressure on them or you will never get them off.

· Un do the 6 - 10 mm headed bolts that hold the bracketry in place.
(DO NOT REMOVE THE CABLES)

You will notice the apps is on the back of the bracketry that you just removed, it is held in place by 2 - 20 bit screws. These screws have a little bit of locktite on them so make sure you have a good socket and gently give a little tap with a hammer before attempting to loosen. Be very careful these screws strip very easily and you only get one shot at them.

· On the apps you will find a white tag that gives you the information on what the apps adjustment should be.

· After loosening the screws you can rotate the apps both clockwise and counter clockwise to get the adjustment you need.

· The reading you took at the beginning of the process on pin # 23 should match the white tag on your apps, if not adjust accordingly.

Dinner

What exactly does resetting the APPS do? Like if you do it the way by just unhooking the battery, ignition, etc?
Thanks

Dinner

crobtex

The APPS is the "fly by wire" accelerator pedal for your truck. The "pot" on the APPS assembly tells the ECM how much fuel the injector pump needs to be putting out when you push the go pedal. Very simple explaniation, but that's basically it.....

phox_mulder

You have a 3rd gen truck, you should be in the 3rd gen forum, procedures might differ for the 3rd gens than they do for the 2nd gens.


phox

2fun

I guess I am confused.....
I thought the 24 valve WAS the 3rd generation??
So this is not correct??

crobtex

I think it goes like this:

1st Gen = 12 valve
2nd Gen = 24 valve with electronics (98.5 to 2002)
3rd Gen = 24 valve with Common Rail fuel system (CP3)

pc12driver

Something to consider when determining which APPS reset is "right":

The "disconnect the batteries" method will force the ECM to re-learn the minimum and maximum voltages from the APPS. That way the ECM can correlate the proper pedal position for idle and full throttle. Typically used (and recommended in the shop manual) after replacing the APPS.

The "voltage adjust" method will allign the PCM and ECM so the transmission will shift and lock up at the proper rpms. The ECM will self adjust, the PCM will not. Once the APPS is reclocked to the at-idle voltage that the PCM is looking for (found on the tag), then the engine and trans will work together properly. Again, something to perform after an APPS replacement or after significant APPS wear on an automatic truck.

Two different procedures for two different reasons. And if you consider that the PCM on a manual tranny truck doesn't even use APPS data, the second procedure is a total waste of time on a manual truck.