Fuel interuption

[Joe_Fensterbau]

Have an '02 3500 5.9 Cummins 6 speed RWD that has an older model Quadzilla tuner installed in it. Few months ago, started to notice a very slight pull back when driving at a very steady highway speed. Problem gradually increased to the point where, once it's been driven for about two hours, it will do it at most any speeds. But if I step into it a little bit, the pullback/fuel interruption won't be felt. The truck runs very well under acceleration, but not with a very slight touch of the pedal after running a couple of hours.

Diesel mechanic disarmed the tuner from the map sensor, feeling that the tuner was making the map sensor not function properly. Ran fine for a few days, but started acting up again with the pullback. Put it into cruise control and it runs perfect. But can't run it long on cruise control, because it will suddenly drop into complete "limp mode", whereas the truck will stay running, but nothing happens when you push down on the accelerator pedal. Have to shut off the truck, turn it back on, hit the pedal once, and on the second push down, it will roar back to life. So can't use the cruise control.

Going to replace the map sensor tomorrow, but am wondering if:

A) Has the tuner ruined the map sensor?

B) Is the tuner just bad?

C) Are both the map sensor and the tuner bad?

Big question is...can the tuner simply just be removed? And does the truck have to be reprogrammed by DoDge after the Quadzilla is removed.

Thanks...any help is greatly appreciated.

 

[Fast69Mopar]

Have an '02 3500 5.9 Cummins 6 speed RWD that has an older model Quadzilla tuner installed in it. Few months ago, started to notice a very slight pull back when driving at a very steady highway speed. Problem gradually increased to the point where, once it's been driven for about two hours, it will do it at most any speeds. But if I step into it a little bit, the pullback/fuel interruption won't be felt. The truck runs very well under acceleration, but not with a very slight touch of the pedal after running a couple of hours.

Diesel mechanic disarmed the tuner from the map sensor, feeling that the tuner was making the map sensor not function properly. Ran fine for a few days, but started acting up again with the pullback. Put it into cruise control and it runs perfect. But can't run it long on cruise control, because it will suddenly drop into complete "limp mode", whereas the truck will stay running, but nothing happens when you push down on the accelerator pedal. Have to shut off the truck, turn it back on, hit the pedal once, and on the second push down, it will roar back to life. So can't use the cruise control.

Going to replace the map sensor tomorrow, but am wondering if:

A) Has the tuner ruined the map sensor?

B) Is the tuner just bad?

C) Are both the map sensor and the tuner bad?

Big question is...can the tuner simply just be removed? And does the truck have to be reprogrammed by DoDge after the Quadzilla is removed.

Thanks...any help is greatly appreciated.

You can remove the Quadzilla just by disconnecting everything it is plugged in to and reconnecting all of the OEM connectors to their corresponding sensor/location. No programming required.

Before you do that, here is more than likely what your issue is...

What is probably happening is severe RF noise interference on the APPS circuits. APPS stands for Accelerator Pedal Position Sensor. There is a noise filter than can be installed that will eliminate the RF interference on the APPS circuits and improve the overall driveability of the truck. I have delt with this issue for years and it affects tuned and untuned trucks alike.

If you connect a scan tool and go for a test drive while monitoring the APPS you will see crazy voltage fluctuations. Those voltage fluctuations cause the truck to do some not so desirable things like lose power for one. On the automatic trucks it make it where the torque converter clutch cannot engage.

Give it a shot. An aftermarket RF noise filter is available for about $25. Also, all of this is dependent on the vehicle being in proper running order IE maintenance up to date, fuel filters good, good quality fuel etc.

 

[Joe_Fensterbau]

Hi Fast69Mopar,

Am appreciative of the advice...will give the RF noise filter a try.

Are you also thinking that the map sensor is not the issue in this case either?

Thanks for the input.