CumminsHokie

By "resetting the apps voltage" I meant adjusting the set screw until my voltage was at 0.63 V and then turning it back 1/2 a turn. I only did the apps re learn because I had just had my batteries unplugged and because I had just messed with the apps adjustment screw to change the voltage. I have my old apps sensor (i know it idled fine when I had it in) so I was thinking about just plugging that in (without installing it fully) and starting the truck to see what my torque app reads for tps. When I did unplug the apps sensor and start the truck I said that I did not hear any change in idle but my torque app finally read 0% for tps. I wouldn't say that it's idling rough anymore but the rpms still seem higher than I remember. In park or neutral, idling, the rpms read about 850. From what I've read this is normal. I need to call timbo again but work has been hectic lately and I haven't had time. I need to make the time.

Gents and ladies, This is my first post on any forum ever but I figured mopar mans forum would be the best. I'm really stuck on what's happening with my truck and it's so annoying because I just got it running beautifully not too long ago. I will start off with some back ground of the truck and the problem. Its a 2001 with about 210k miles, 2wd, automatic trans, bhaf air filter, 4 inch straight pipe, and until recently (I took it off thinking maybe it was causing my issues) an old quadzilla adrenaline that replaced my super chips (I say old because it is one of the first boxes made and I got it used, had the big power resistor replaced, then tested at quadzilla and verified). Now the problem started about a week ago when I noticed that my rpms were kind of bouncing around at 1000 when coming to a stop from higher speeds. I would be doing about 50 and then let off the accelerator pedal, apply brakes, and once in maybe 2nd gear the rpms kind of bounced at 1000 and you could hear it in the engine. They would then return to about 750 once below say 10 mph. This happened for 2 days and on the second day I arrived home and placed the truck in park and noticed it was idling at 1000 rpms. I also noticed a very random, intermittent spike in the rpms as it sat there idling and could hear it in the engine. I'm not sure what a miss sounds like but that's my best guess. This is when I removed my adrenaline. The next day the problems persisted and I noticed that the truck was running rougher than usual. I hooked up my scan gauge 2 and saw that my tps was at 1 and was spiking to about 12 at all times. Once above 12 or so it would stop spiking. As a quick fix attempt I turned down my timbo apps until the rpms sounded about normal and then reset/calibrated the apps. The tps is still stuck on 1 and spiking to around 12 randomly. I recently replaced my iat sensor (not with a CUMMINS part) as it was faulty and was causing dead pedal issues so I unplugged that thinking the cheap sensor I bought was causing it. No luck. I then unplugged my map sensor as I've read many times that this cause rough idling. No luck. It has also been cleaned recently and seems to be functioning properly per my scan gauge. Since readjusting my apps the rpms have come down a little but are still high in park and neutral only(goes to normal when in drive). The only other information I could see worthy to include is that when I had the quad on I didn't tap the pump wire so I only had levels 0-2. When driving with it on 2 or 1 I noticed what seemed to be the tc locking and unlocking and it got more noticeable as the levels increased from 0-2(can't really feel it with it on 1). I assumed this was because it is an old box but idk that it could have been creating additional ac noise? I havent been been able to do any troubleshooting but when I get time this weekend I will be first checking the alternator for excess noise (even though it's fairly new) and then testing the entire apps harness per instructions found on this site. The only other thing I can think to check is the camshaft position sensor. Any thoughts? I have no codes being thrown and no dash lights illuminated. Any suggestions would be greatly appreciated and I really want/need to get this thing fixed. She's the love of my life. forgot to add that I also have a raptor 100 and gauges, though glowshift. Fuel pressure has always been 18 at idle and 16 at wot. It seems to be a little lower now from what I assume is because the truck is idling higher. It sits closer to 17 idling in park.

Sorry I haven't been able to post much of an update, been very busy getting my Jetta tdi ready for daily driving so I can start heavily modding my truck. But first I still have issue to resolve. Since cleaning the grounds, resetting the apps voltage, and doing an apps re learn the truck has been running much better. No "hickups" at idle, the rpms at idle have dropped some to about 850 and, whether its related to the apps sensor or cleaning the grounds, the truck just drives like a whole new truck again. So for that, I thank you guys. With that being said I noticed that my torque app was still showing 12-13% for TPS so I called Timbo. Also I did unplug the apps and was not able to notice any changes in sound or idle but did notice that Torque app now showed 0% for TPS. We talked through the problem and he mentioned that the apps voltage is dependent on a good ground and that the ground determines the voltage. I thought it was interesting since my harness going to the apps connector had the crappy splice job with a wire going to the negative terminal of the battery. Im wondering if the connection has become compromised. I will hopefully be returning the wiring to stock this weekend assuming I can borrow a deutsch tool from work tomorrow. If returning the wire to stock does not work I will have to move on to other things. I recently stumbled across a thread where they talked about rewiring and splicing in wires between the apps and ecm and pcm. Any input on this? is it just to fix TC locking issues or could it potentially help me with my apps issue? I have pasted a link to the document from ats below. https://www.atsdiesel.com/PDF/120505/4th hunt 46 47 RE.pdf

Thanks @Dieselfuture I'm thinking I'll get a new one online and rebuild my current one so that I'll have an extra for down the road. I don't ever plan on selling my truck so it can't hurt.

Roger that. I'll have to look into it. Well I'm not sure to be honest. I believe that the engine idling high was due to the apps being at 17% but I can't say for sure that the engine rpm increase was proportional to the 17% or the increased apps voltage of about 0.9xx volts.

How's the process of rebuilding an alternator? Need any special tools? Is it good enough to rebuild the one I bought from the local parts store?

I think I was thinking of testing the idle validation switches. I reread that article and now it doesn't seem as applicable. Anyone have any suggestions on a good alternator? Or is it more along the lines of just don't buy a reman?

I cleaned my battery terminals as a part of cleaning all the grounds. Is that enough to satisfy g115 or should I get spray the plugs with contact cleaner? im glad I joined this forum and I really appreciate all of the help! @Mopar1973Man you've done a write up on testing all of the apps connections haven't you?

Roger that, I've got batteries disconnected now, gonna do a reset and then check the voltage again. It still seems to be idling a little high and rough but definitely better. I just cleaned all of my grounds while I had the free time. so should I be in the market for a new alternator? Any suggestions? I'd like to up the amperage output a little if possible without spending way too much money

Okay a few questions. 1.) what would cause my apps voltage at idle to randomly increase to .93? 2.) should I look into replacing my alternator soon if the ac reading was 0.1 volts while the grid heater was cycling? And because I read 0.03 v at 160* coolant temp. 3.) what's to say my tc won't start locking and unlocking really badly when I pull off the noise isolator? as for the ground wire added into the apps sensor by the PO, the harness is pretty jacked up, I'm going to try and borrow a Deutsch kit from work and remake that's plug.

Ac voltage read at the alt was 0.03 v with the truck almost at op temp. The grid heater was kicking on and it'd ramp the ac noise up to over 0.1 v is that normal? I've got 14.16 v Dc coming off the alt and 14.11 v measured at driver side battery. I installed a timbo apps. i revved the rpms a little and then the truck started idling very rough. Here's a video IMG_1073.MOV I also think I just found an actual ac noise filter. It's a wire going from a ground to the pcm?(passenger side computer) and the wire has components in the middle. I think it's a bd noise isolator.

I replaced the apps about 6 months ago when chasing down a dead pedal issue. The wire is on the "truck" side of the harness, meaning the main harness side. I will check for ac noise and report back.

so would it be safe to assume my apps is the culprit? i was just looking at it and I noticed that the PO added a wire from the apps harness to the negative terminal of the battery. I'm not sure what wire it's connected to as it's pretty crapily covered in electrical tape but any ideas what he was trying to do there? Makeshift Apps noise isolator?

So I get my obd2 reader all hooked up and start my truck and the first thing I see is that my throttle position is stuck at about 17% (fluctuating above and below 17). I'm using torque pro btw. Interesting that 17 is what my scan gauge was spikeing to when at idle. So now my question is what is that 17% is it what the ecm is requesting or what's being requested of it?

Thanks for the optimism dripley! I was actually just monitoring it again and it seems to have jumped up to 17% not that that matters I don't think. I wondered if it was just a scan gauge thing. I'm excited to get the obd2 reader and see what I can find. also just an FYI since I assume we are all cummins fans here. That haul truck in my picture has a cummins QSK60 16 cylinder diesel that outputs about 11 times what our trucks do stock, hp wise. That thing is the Maserati of the haul truck world.

Just ordered a BAFX OBD2 bluetooth scan tool and it will be here tomorrow. It had good reviews and seems like it is somewhere in the middle of the two that you suggested, quality wise. I will download torque pro unless you all suggest a better alternative.

Unfortunately it just has the pod. Ive been brainstorming ways of monitoring the tps but i cannot think of a secure way that doesnt involve wire tapping the harness on the apps side. Which isnt a huge deal i just would like to avoid it if possible.

I just recently graduated and had the craft of scientific writing beaten into my skull only to continue using it with my job...who would have thought?! The dead pedal issue happened about 6 months ago and was taken care of by replacing the IAT sensor. I have done most of the work indeed and i did mention codes, but the lack there of. I too am wondering if my apps needs replacing but it would be odd as it is only about 6 months old as well. There seems to be a link with the apps as the truck drives completely fine except for when i am decellerating from higher speeds and the rpms get stuck at 1000 until about 15 mph where they begin to come back down to normal idle. Other than that the truck feels greeat when driving around. I like the scan gauge but i find that its very low sampling rate (i assume) makes it near useless for real time debugging. How would i check the resistance of the apps? Just hook up between the supply wire and output wire of the apps? I have all sensors plugged back in at this time. Unplugging them was only to try and facilitate some type of change in its behavior. I call it old because it has the old circuit board thats more prone to burning up (especially the big white resistors - my box only has one of tthose). Does your statement still stand, i would love to make it more badass! Im hoping to get this resolved, and i appreciate all input. Watch out now, my truck and i are both millennials and could easily be triggered by anything you say...ANYTHING!!! LOL just kidding, she's definitely a girl, just a rugged looking one...i call her gertrude. Shes not the prettiest but has a great personality...most of the time. Here she is hanging with her big sisters.