First off moparman, I apologize for emailing you with this the other day, i didn't see until it was to late that you have on here you request people to post rather then message you, i'm signed up now :banghead:.I have an 02 with the HO Cummins and I recently added the Quadzilla XZT module wanting the high idle feature. I hooked it up and I got the power advantage, but high idle woudln't activate. After many emails to Quadzilla and them being very willing to help figure it out, they asked me to send it back for them to look at it saying it must be the module itself. I should add they said it may be my APPS sensor not being at zero at idle and the module wouldn't kick into high idle if it wasn't, so i had it checked and it was zeroing. Now,they sent me a new programmer even though they couldn't get mine to act up for them, rather than making me wait any longer, I hooked it up and guess what, no high idle! Looking back at when I had my mechanic check the APPS, I don't recall him having the truck running when he checked it. His diagnostic computer said It was on zero and the posistion reading changed when pushing the pedal but I am sitting here now wondering if maybe it would read different when idling, making it not at zero ? I also notice that the cold engine protection feature in the 2011 download I have on the module doesn't work like it should and I can get the horsepower gain on a cold engine if i want it. Anyone have any ideas or thoughts as to why the high idle wont work? I hate to keep bugging Quadzilla because apparantly it must be something with my truck and not the module since two modules act alike.

welcome dobienut, i have also noticed that my 99's apps doesn't ever read 0% at idle. i also notice that i never get to 100% this thread has links to the spreadsheets(there are 3 highway drives)http://forum.mopar1973man.com/showthread.php/1275-data-from-my-drive-on-the-highway. if i get a nice enough day, i am going to reset my apps. have you tried resetting yours?http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps.htm

Just came in from resetig the APPS, started it up and waited for my programmer to kick into high idle and nothing . Other than going to a Cummins mechanic I have no was of telling if it's at zero, but seeing that the high idle isn't working i'm guessing it's not. Soon just going to say the heck with the idle

Ok here is a tidbit...

http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps.htm

Now take notice the APPS sensor has 2 idle validation switches. If the switch states are in the wrong state high idle, exhaust brake, and idle RPM's will be wrong... But the funny part is the APPS will still show 0 TPS on a data tool. But it more important to get the state of the switches correct.

Now I'm going off on a limb I don't like to...

1. Is the APPS old or wore out?

2. Is the APPS producing error codes (P0121, P0122, or P0123)

If ANY of these thing are occuring replace the APPS sensor...

http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps-replacement.html

Your going to need a DVM...

Now as for the APPS idle validation switches they are done electronically inside the APPS sensor. They detect the voltage of the rheostat and determine if its at idle or not. On the back of the sensor is a tage with voltage on it. You wan to check the voltage of the APPS at the ECM (not the PCM). Then using the set screws adjust the voltage till you hit your mark. The wire color and pin number are listing on the pic above...

There is several write ups about the Torx screws in back and moving the sensor. Don't bother with that... Just use the set screws on the front much easier to do... As for the voltage double check it after flicking the throttle rapidily if the voltage changes a bunch at idle then the APPS is most likely wore out or wearing out... But if you flick the throttle and the voltage is still set at what the sensor tag shows your good.

Now do a APPS reset and try it again...

Thanks MM for that. The apps is more than likely as old as the truck because i've had it for 6 years now and I haven't touched it, so more than likely it was never replaced before that because there wasn't alot of miles on the truck when I bought it. I know to some it may be easy checking the voltages but I think i'll have to get a mechanic to check it because i'm nothing with a volt meter :banghead: Worst part where I am, you have to kiss someones a** to get them to look at a small problem like this apparantly because I have called a Cummins mechanic three times so far to see if he can fit me in and i don't even get a call back. Must be nice to be so independant

Don't call Cummins or Dodge for a APPs sensor... It will cost about $400 buck (or $760 Canadian)... I would call either Jocob Kidd Diesel Auto Power (which happens to be a vendor here) or contact Timbo Directly for a Timbo APPS. They are costing $160 bucks for a replacement... http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps-replacement.html

i reset my apps (and cleaned those terminals up) and noticed a little extra "umph" from the seat of my pants. before it "had no power" below 2k rpms. now it is smooth through the band. i will mention that when i jumped into the cab, i had to set the time on the radiio. i started programing the stations (since the radio started on am), but they were still programed! i have to wait to check obd values as i don't have a laptop or dyno.:banghead:as far as finding someone to check your volts... i have always hated chasing peoples ghosts....not everyone is like this example, but some people get a hunch, even if its not right, and will not accept logic. you can explain that _____ passed every test possible, but because they read something on the internet, their daddy always said, they were in the biz for years and KNOW, (insert BS excuse here). and won't except that the problem is else were. because of a few annoying people, i avoid problems like that. it is far easier to fix things that are broken than to chase electrical. i am not saying you are the example...i mean that because of people like that, i avoid that work. when your independent, time is money:2cents:

Don't call Cummins or Dodge for a APPs sensor... It will cost about $400 buck (or $760 Canadian)... I would call either Jocob Kidd Diesel Auto Power (which happens to be a vendor here) or contact Timbo Directly for a Timbo APPS. They are costing $160 bucks for a replacement... http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps-replacement.html

Nice to know, dealerships charge way to much for parts ..Thanks MM

Edited February 10, 201015 yr by dobienut

Sorry to keep beating this thing to death, but if you look back at my first post I commented saying that I have noticed this programmer has cold engine protection on it so it wont produce the HP gain until desired temp is reach in the motor. I have noticed a few times, one being this morning coming home from work that I had full HP gain when it was dead cold , which leads me to believe the programmer isnt doing what it's suppose to. As I said, this is the second programmer so I can't see both acting the same, i'm just wondering if I should be looking somewhere other than the APPS sensor. Anyone had any dealings with the XZT and had any issues?