Archived Getting Trouble Codes in Conjunction with loss of power

[dannyh]

Lately I've been having my truck lose power suddenly and causing the check engine light to come on. The codes are P0234 Mod $15 Engine overboost condition and P0121 Mod $15 TPS/ Pedal Position Sensor A CKT Range/ Perf. This has happened several times and I still can't identify common variables that cause it to happen. I have thus far come out of it by feathering the accelerator back and forth and it will continue as though nothing happened except I have a check engine light on. I have a 2000 w/automatic transmission. These trouble codes always come on in conjunction with each other. Does anyone have any thoughts on this. Any help would be much appreciated. Thanks,



Dannyh

 

[Alan Reagan]

Do you have any mods on the truck?



Sounds like the TPS is going bad. The overboost code is being set by the MAP sensor. Either one failing can cause the problem you are having. The MAP sensor failing will cause the engine to defuel when is see's an overboost condition. The TPS will hit a bad spot and it's like letting off the accelerator.

 

[dannyh]

Thanks Alan for your response. Sounds expensive! The truck is stock (no mods). Your description sounds like what I'm experiencing. Is there anything that can be cleaned or is it strickly replacement. Also is there a way to isolate the MAP sensor or the TPS as the problem?

 

[Alan Reagan]

http://dodgeram.org/tech/dsl/mt_2_feb98/fuel_sys_comp.htm



will show you where the MAP sensor and TPS is.



Cleaning the MAP sensor has varied success rates for solving this problem.



The TPS is around $325. Are you under 100K Miles? It may be covered under warranty.

 

[dannyh]

Hi Alan. I have 130,000 miles on the vehicle. My initial thought was the TPS so I went to the dealer who looked it up for cost and he couldn't find what was called a throtle position sensor but rather a bell crank or APPS. He seemed puzzled. Anyway the price he came up with was $487. Thanks again for your response.



Dannyh

 

[Alan Reagan]

He's right on the terms. On the 24 Valve, it is the Accelerator Pedal Position Sensor. It's #18 on the link I sent to you.



You can get them for about $325. $487 is full list from the dealer. One thing that may help is to reset the APPS until you can get one.



Here's how:



http://www.dodgedieseldatabase.com/apps.htm

 

[dannyh]

Hi Alan. I appreciate the time you've spent with me and my problem. Where might I find one (APPS) for the $325. That sounds better that the full list price. Hope you have a great day! Thanks again.



Dannyh

 

[Alan Reagan]

Scroll down to the post by Evan A. Beck:



https://www.turbodieselregister.com/forums/showthread.php?t=139865



Contact him to see where he got his. Either PM him or contact him through the email on his signature. He says about $350. I have seen them for $325 but it's been a while and I can't remember where I saw it. Of course, there might have been a price increase since I was looking.

 

[CSnyder]

I have been getting the exact same codes on occasion but it only does it to me in the morning. I reset my codes and won't have a problem all day long. I have recently replaced my APPS so I know that is not the problem. I have narrowed mine down to the Map and or IAT. I would try those before spending 350 for an APPS as they are much cheaper. If you have any questions you can reach me at 563-419-0252 Chris

 

[Alan Reagan]

I have been getting the exact same codes on occasion but it only does it to me in the morning. I reset my codes and won't have a problem all day long. I have recently replaced my APPS so I know that is not the problem. I have narrowed mine down to the Map and or IAT. I would try those before spending 350 for an APPS as they are much cheaper. If you have any questions you can reach me at 563-419-0252 Chris

I don't disagree with that at all. Usually when the IAT is giving you a problem you just get more smoke than usual. Also, they need to be cleaned occasionally to get the carbon off so that it is not insulating the thermistor which is responsible for the temperature measurement. The APPS usually goes at about 155-200K miles. That's why I'm thinking.



Looking on another post in the 911 section today, one of the guys responded that you can get an APPS through NAPA for $168. Alan

 

[PatrickCampbell]

Any PN on the APPS?



I can't figure out if I toasted mine or not--was playing with it trying to setup a high idle and ended up plugging it in and unplugging it a few times with the ignition on. Now it is reading 4. 0 V at idle instead of 0. 5 V. Wait to start light is flashing -- I won't try starting the truck.



Trying to clear the codes and see if it "resets" itself hopefully. :{