APPS low voltage p0122

[Frankstein]

Hello guys, I've just returned from a road trip and check with my edge JWA trouble codes and found a p0122. I notice a change in APPS % .   I set it and got 0% at idle but after around 1 month now I have like 3-4% at idle and when colder with intake heater cycle, its 5-7% idle and drop to 0% when grid heater is on, after goes up to 5-7% ..   Now I'll try to disconnect the batteries and try to relearn the APPS!       Can it be the APPS begin to get tired? I changed it 2-3or4 years ago (dont remember) with an APPS from rockauto!    

 

If I need to change the APPS wich one do you recommend me?  best for cheap!!   or simply the best that will last more.  Thanks

[notlimah]

If you're going to replace it, it's best to go with Timbo, but others like the electronic one from NAPA I think it is. Have you gone through the process of verifying your APPS voltage to make sure it didn't get all outta whack?

[leathermaneod]

I haven't heard of any from Napa, but guys talk about the Wells version that is sold by autozone under the name Duralast. I have one. They have a lifetime warranty and are operated magneticly so there are no contacts to wear out. Tricky thing with them is having to set it to the correct voltage. They are also more expensive than the Timbo. The benefits are that it is non contact, so should in theory, last longer and it has a lifetime warranty. Downside is that it costs more and takes more work to install and set properly. If you decide to go with wells, let us know and I can give you some tips on getting it set right.

Edited June 19, 2016 by leathermaneod

[notlimah]

Thanks for clearing that up @leathermaneod I knew I was thinking that, just couldn't get it out! haha

[leathermaneod]

No problem btw, how do you tag people in a post like that?

[Frankstein]

Thanks guys I'll check it.  I've just do the apps reset and check the voltage. I'll see if the code come back in next days!!    

 

Wells is the company of the sensor?   I'm from Quebec,Canada and don't think we have Autozone!!!

[leathermaneod]

Yes, it is Wells Vehicle Electronics. If you don't have autozones, you may be able to order one online from them, although then you wouldn't have the convenience of just taking it to the store to swap out for warranty issues. Also, not sure how you are checking the voltage, but when you do, it should be at or below the voltage on the sticker on the back of the sensor. 

[Frankstein]

@leathermaneod,   The one I buy is Airtex # 5S5352 from rockauto around 3 years ago!   I think its the same you talk??   Yeah it got me the same number .....   In the back it dont have sticker for voltage adjustement!!??

[Mopar1973Man]

About the Wells and OEM APPS they both have the same weakness to AC noise and electronics failure typically show as a P0121, P0222 or P0223. So it might not wear out because of a magnetic sensor (no contact) but a Timbo's is completely electronic free. The problem with the Wells and OEM APPS is its still based on voltage to toggle the electronic IVS (Idle Validation Switch). Timbo APPS is fully mechanical IVS switch no electronics. Which way to go is up to how deep your pockets are. Wells is for sure more expensive than a Timbos...

 

I've just got my two extra Timbo's APPS. I made a request for this exact reason so he sent me two APPS sensors to play with. So here shortly I'll be popping open a Timbo's APPS to show the guts and the fact there is no electronics to fail. Yeah the rheostat might wear out but 5-7 years down the road.

 

Here you go...

Edited June 19, 2016 by Mopar1973Man

[leathermaneod]

33 minutes ago, Frankstein said:

@leathermaneod,   The one I buy is Airtex # 5S5352 from rockauto around 3 years ago!   I think its the same you talk??   Yeah it got me the same number .....   In the back it dont have sticker for voltage adjustement!!??

I honestly don't know if the airtex from Rock Auto is the same or not, but I would doubt it. If you don't have the original to know what voltage you need, I would guess you would just set it as close to .5v as possible and see if you have issues. You should be able to tell with your Edge wether it is throttling when it shouldn't be or not. If I were in your shoes, I think I would just go with the Timbo.

 

22 minutes ago, Mopar1973Man said:

About the Wells and OEM APPS they both have the same weakness to AC noise and electronics failure typically show as a P0121, P0222 or P0223. So it might not wear out because of a magnetic sensor (no contact) but a Timbo's is completely electronic free. The problem with the Wells and OEM APPS is its still based on voltage to toggle the electronic IVS (Idle Validation Switch). Timbo APPS is fully mechanical IVS switch no electronics. Which way to go is up to how deep your pockets are. Wells is for sure more expensive than a Timbos...

 

I've just got my two extra Timbo's APPS. I made a request for this exact reason so he sent me two APPS sensors to play with. So here shortly I'll be popping open a Timbo's APPS to show the guts and the fact there is no electronics to fail. Yeah the rheostat might wear out but 5-7 years down the road.

 

Here you go...

Thanks for jumping in Mike! Honestly, I think if I had it to do over, I would go with the Timbo over the Wells just for simplicity sake. I do like to get away from electronics when I can. Someone on another forum, I wont mention names here, talked me into the Wells. It wasn't exactly bad advice, but had I known what I know now, I think I would do things differently and get the Timbo.  If you remember Mike, you and I had a phone conversation about this. Depending how long my current Wells lasts, I may switch to the Timbo when it dies and give the Wells to you to cut open, assuming you would want it.

[notlimah]

1 hour ago, leathermaneod said:

No problem btw, how do you tag people in a post like that?

 

Type in the @ symbol and wait a second and names will pop up. So if I type @lea your name will show up on a little drop down menu and you select what name

you want and it'll automatically pop into your post highlighted blue and tagging the person 

 

I'll throw another vote in for timbos apps. Never heard of any problems coming from it other then people messing up the proper voltage settings. 

 

[leathermaneod]

Thanks @notlimah. Sweet it works! Lol yeah now that I know how the different apps' work, I'd go with the Timbo. Seems like that would be super easy to set especially with something like a scanguage or edge monitor that tells you the throttle position. And even without you can't really go wrong. I had one heck of a time getting the wells set where I wanted it!

[Mopar1973Man]

I peeled the wiper hub out of the rheostat to sho the IVS section and how i works. Look at the previous picture there is a set of wipers on both sides. On side is for the throttle value the other side is for the IVS (Idle Validation Switch). As you can see as throttle increases the wipe moves from one to the other in contact bridge to a ground pad. This is way handles the IVS signal to the ECM.

 

 

So this shows the simplistic design of a timbos where its nothing more than a rheostat and a contact patch for the IVS.

 

 

Much better than this from the OEM... Wells is no different really.

[leathermaneod]

The only thing I still would like to know about the wells is, why mine works correctly even though it is set slightly higher than the .497 that was on the sticker for the original. Mine is set at .505 and idles fine. Goes into high idle just like it should and the scanguage indicates 0% throttle other than the occasional blip that others have confirmed is normal. I tried to talk with bigfish about it on CF the other day, but he is convinced that as long as it is below .519, your are good to go, which doesn't make sense with the sticker voltage, but it would explain why mine works just fine...

[Mopar1973Man]

More... Here is a close up of the wiper. Like little hairs...

 

Again... Voltage is NOT suppose to be set to the tag of the OLD APPS. That is wrong. The voltage has to be set for IVS to be in the idle state. This is why I don't suggest OEM or Wells because people assume way too much in voltages and screw everything up. The IVS is trigger by a preset voltage to toggle between ilde state and throttling state. So that what the electronics do is control the logic betwen idle and throttling. What you need to set for is the IVS voltage for Wells APPS not the old OEM.

 

Here back to the Timbo's there is no voltage adjustment because the IVS is mechanical and the mere angle of the bellcrank is what toggles the IVS from idle to throttle.

Just for fun here is the best picture of a Wells APPS I could find. As you can see it still electronic but there is no contact because it uses a magnet for the position. Still the IVS is voltage driven so proper calibation of the idle voltage MUST be done to the Wells specific not the old APPS sensor. As you can see it still based on IC chip to handle the logic of the IVS switch.

[leathermaneod]

Oh ok now that makes sense why Wells tells you to set it between .5 and .6. Also explains why mine, set at .505, works just fine, although I wish I hadn't been talked into lowering it, by that person on CF, from .55 where I had it originally. I like to have some wiggle room. Makes me want to go back and adjust it again, but it's such a pain in the butt, I guess as long as it works I should just leave it be. Then when it stops working, I can order up a Timbo 

Edited June 19, 2016 by leathermaneod

[Mopar1973Man]

Lower is better but this give technically more throttle slack. This why on the Timbo's you adjust the stop screw till the voltage rises then back off again and add 1/2 turn back yet to the stop screw. This puts the APPS as close as possible to the THROTTLING position without being too close.  The whole idle voltage set has nothing to do with idle speed (Internet myth). Like my high idle kit and exhaust brake are based on the IVS state. If the IVS is in IDLE position then the exhaust brake and high idle features work. IVS in THROTTLING mode then neither devices will work. This is why its stated you can not adjust the idle speed of the engine because once IVS selects IDLE position then the APPS voltage value is totally ignored and the on board ECM software controls idle from that point on. Idle speed is calculated from ECT offset. So in my own testing if you decrease ECT it will raise idle speed or if you increase ECT then the idle speed is lower. Once the IVS flips to THROTTLING mode then the ECM runs strictly on the APPS commanded voltage value.

 

So back to where this person claims that idle voltage has to be set at .5xx volts is false for Timbo's. But holds true for Wells and Stock OEM APPS because the IVS state is based on voltage.

Another though you say its difficult to adjust. Again people are adjusting this all wrong. I gather your adjusting from the back side with the two mounting screws? Again this is wrong. Just use the set screws in at the bellcrank to raise and lower the idle voltage. Then the WOT stop pin you can adjust too. The reason why it wrong to adjust from the back is because you altering your WOT and IDLE setting within the set span of the set screws. So if you raise idle voltage from the back then your also raising the WOT voltage and visa-versa. I'm going to find out how far the WOT can be set and see if I can get a safe high and low voltage range for APPS sensors. So make your life simple use the stop screws and not the beck side twisting the sensor.

[leathermaneod]

Very helpful info here Mike! I had no idea it was wrong to adjust via the screws in the rear. It seems you may have learned some new info since we had our phone conversation about this....I'm confused though, how do you know where to set the sensor in its oblong holes when you replace it if your not going by voltage? Or does it not matter? You are saying to just install the sensor, and then adjust via the setscrew until the voltage is where you need it according to the Wells instructions? Is my WOT voltage set too high now with my idle voltage at .505? What exactly happens if WOT voltage is too high? Will rev limiter no longer work? Sorry for all the questions. I'm starting to see now why you are such an advocate of the Timbo APPS. I didn't realize there were all these unknowns when you go adjusting that voltage. I guess it would be even more troublesome with an auto trans. Hopefully I don't have anything to worry about with mine since high idle still works....do you think I do?

Edited June 20, 2016 by leathermaneod

[Mopar1973Man]

44 minutes ago, leathermaneod said:

What exactly happens if WOT voltage is too high? Will rev limiter no longer work?

 

If the WOT position is too high then it will trip the P0123 APPS volts too high then dead pedal on you.

45 minutes ago, leathermaneod said:

I didn't realize there were all these unknowns when you go adjusting that voltage.

 

Most of this was learned from dealing with people doing it the wrong way and then creating bigger problems like this old CF article.

http://www.cumminsforum.com/forum/98-5-02-maintenance/13542-apps-adjustment.html

 

This article will create all kinds of problems because typically your end voltage at the APPS will be too high and create problems for auto transmissions, high idle kits don't work nor does the exhaust brake. So this prompted me to learn and understand how the APPS sensor truly worked and then re-write the article here.

 

 

49 minutes ago, leathermaneod said:

Hopefully I don't have anything to worry about with mine since high idle still works....do you think I do?

 

No you don't. IVS is toggling properly for you so really there is nothing to worry about. It's when it quits working you start to worry.

50 minutes ago, leathermaneod said:

I'm confused though, how do you know where to set the sensor in its oblong holes when you replace it if your not going by voltage?

 

Again your trying to match range of motion to range of voltage. So the trick here is to make sure you can reach both your lo to hi volt range. I'm going to take some time in the future and do the testing for extreme limits of the APPS and create an article that will be more enhanced version of the basic voltage adjustment above. The lo volts is going to be tough being both mine and the the two extras are from 0.4xx to 0.6xx volts range. The hi volt spot I'm going to push mine as far as possible to find it.

58 minutes ago, leathermaneod said:

I had no idea it was wrong to adjust via the screws in the rear.

 

Take notice to the Timbo's APPS it not slotted in the mounting holes. Now look at the OEM and Wells APPS are both slotted and adds to the whole adjustment problem. On the Timbo's you just bolt it up and then set your idle stop screw. Wells and OEM you've got to find that range of motion that gives the most to the both.  If you can get at least close then the rest should be good.

[leathermaneod]

Well I'm sure everyone will be very greatful when you figure this out! Although if we all just took your good advice and went with Timbo we'd have nothing to worry about. I hope mine lasts at least as long as the oe did and doesn't die at a super inconvenient time....at least I know I can fix it on the road if it does. Makes me wonder if mine would throw a code if I took it to WOT? I'm not sure if I have since installing that. Although since I have it set low, I would think it would be ok....