P2121 P2122 P2123 no throttle response - Dodge Cummins Diesel Forum
- HOME - FORUMS - GARAGE - TECH - ARTICLES - CHAT - CLASSIFIEDS - REVIEWS - VIDEOS - MEMBER MAP - STORE - INSURANCE -
- REGISTER - CALENDAR - INFO - SITE HELP - RULES - STAFF - MEMBERSHIP - ADVERTISE - CONTACT US -


Welcome to the Dodge Cummins Diesel Forum, the fastest growing Dodge Diesel Community on the internet.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us
Go Back   Dodge Cummins Diesel Forum > Technical Articles - Writeups - Guides Section > 3rd Gen Tech Articles
3rd Gen Tech Articles Tech Articles for the 5.9L 3rd Gen Dodge Cummins Diesel...NO ADVERTISING

CumminsForum.com is the premier Dodge Diesel Truck Forum on the internet. Registered Users do not see the above ads.

Auto Insurance

» Featured Product
Wheel & Tire Center

Closed Thread
 
LinkBack Thread Tools Display Modes
Old 11-07-2007, 05:30 PM   #1 (permalink)
Newbie
 
Join Date: Oct 2007
Posts: 28
Thanks: 0
Thanked 2 Times in 2 Posts
iTrader Score: 0 reviews
P2121 P2122 P2123 no throttle response

Have a 2003 6spd 2500. From day one, the truck had that irritating rough running at cruise speed. Finally, it became so bad the truck was unsafe to drive (like 70mph bumper to bumper, hit the gas, no body home...).

I did searches all over the internet. No direct "hits" on P2122 (the common error code mine threw). APPS low. My truck's problem seemed to stem from the accelerator pedal position sensor (APPS). Oddly, at the last there, the truck would only run smoothly with the cruise control ON (yes, ON).

I found out the replacement sensor was in the neighborhood of $700 from Dodge, and I wasn't about to drain my bank account on a 'hunch'. This is what I did TO FIX MY TRUCK.

I found the APPS setting procedure on another forum. I bought a digital voltmeter first. Key on, engine off, I checked the output from the APPS sensor plug, using the yellow wire as "+" and the battery ground as "-". I saw .52 volts. The tag on the APPS said 0.535 volts. Easy enough to change: the APPS has 2 locktited Torks bolts, very fragile, but with deliberation, I was able to loosen them, and readjust the APPS to .54. Cleared the trouble codes, pushed the gas to the floor (key on engine off) and let off, turned the key off and on, started it up, and went out for a drive.

And it ran well. For the first, oh, 10 miles or so. Then the truck started running rough again, like it was trying to defuel or something, at 45mph, and then the check engine light lit, the throttle pedal went dead for about 5 seconds, then it "woke up", but still ran rough, like a mind of its own.

Trouble codes P2121, P2122, P2123 again. All pointed to a bad APPS.

I disconnected my Banks 6 gun and reset my Rokk sensor to stock timing, cleared the codes, and tried again. To no avail. The rough running wasn't as rough, but it still threw the codes, the pedal died and came back, same ol thing.

I read somewhere on the internet about noise on the APPS signal and how somebody put a capacitor inline and fixed theirs; however, I lost that link in the meantime, and ended up being inventive.....

Went to Radio Shack. Bought a 220 uf capacitor with no polarity, and a soldering gun kit, spent $10. Back at the truck, I unplugged the APPS wiring harness from the APPS. There are 6 wires. The power comes from the yellow one, and I found the green with orange tracer is 'ground'. I put the capacitor across those 2 wires, buttoned it up, cleared the codes, and tried again.

It has not thrown a code since. Not even a hiccup. Runs really really well. The only drawback I found is that the pedal input has like a subsecond lag to it now. So, if I go to shift like I used to (depress the clutch at the same time I let up on the gas), the engine revs a bit (kinda like the Banks at level 6). I had to relearn how to shift!

Now I let completely off the gas. When I anticipate the audible 'kick' sound from the gas pedal, I begin to engage the clutch. No extra reving. In traffic, the truck feels like it has a lot of extra punch, mostly due to the induced lag now from the capacitor, I guess.

Maybe I should try a 100uf. But hey,....

I just saved myself a $700 repair bill for $10.

Hope this helps anybody frustrated with rough running of their 3rd gen.
spinlocker is offline   Quick reply to this message
The Following User Says Thank You to spinlocker For This Useful Post:
TKO41 (11-25-2012)
Sponsored Links
Advertisement
 
Old 11-08-2007, 03:46 PM   #2 (permalink)
Only in a HEMI
 
BBRam's Avatar
 
Join Date: Jan 2006
Location: Chelsea MI
Posts: 31,541
Thanks: 1,703
Thanked 1,481 Times in 1,028 Posts
iTrader Score: 13 reviews
Thank's for the info. spinlocker. :thumbsup
__________________
2012 Ram 2500 5.7L HEMI
2012 Dodge Challenger SRT8 6.4L HEMI
BBRam is offline   Quick reply to this message
The Following User Says Thank You to BBRam For This Useful Post:
cjewellz (01-23-2012)
Old 03-12-2009, 06:53 PM   #3 (permalink)
Newbie
 
Join Date: Oct 2007
Posts: 28
Thanks: 0
Thanked 2 Times in 2 Posts
iTrader Score: 0 reviews
As time has passed.....

The lag reappeared. I found a procedure where you drill a hole in the APPS and inject plain ol layin around electrical cleaner. This also worked just fine. I don't know exactly where the procedure is found or which forum, but it does exist.
spinlocker is offline   Quick reply to this message
Old 03-12-2009, 06:54 PM   #4 (permalink)
Newbie
 
Join Date: Oct 2007
Posts: 28
Thanks: 0
Thanked 2 Times in 2 Posts
iTrader Score: 0 reviews
Ah, here it is.....

Anatomy of an APPS - TDR Roundtable
spinlocker is offline   Quick reply to this message
The Following User Says Thank You to spinlocker For This Useful Post:
MUDD (06-23-2012)
Sponsored Links
Advertisement
 
Closed Thread

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Dodge Cummins Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Powered by vBadvanced CMPS v3.2.2

All times are GMT -4. The time now is 12:14 PM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.

SEO by vBSEO 3.3.2