I have a '99 1 ton, automatic that had a TPS sensor code show up, and now has no power. I haven't replaced the TPS yet, so could this loss of power be related to the bad TPS? It lugs and takes about 2-3 miles to reach 65 MPH. At 40-45 MPH it will buck as if the tranny is trying to shift in/out. I can shift out of overdrive and get it to go a little better, but will still lose a lot of power if I don't keep the RPM's up. I replaced the fuel filter and air filter when it first showed signs of the loss.

 

I also have a '99, 3500 CTD dual wheel pick-up with a 5 speed and 131k miles. Second inj. pump. I am fighting the same problem and have been for 6 months. It has quit on me a couple of times as I am passing a vehicle and is not a safe way to be driving. The problem can always be "reset" by clutching and letting the engine go to idle for only a second or two then returning to operating speed. I changed the APPS (throtle position sensor) and the trouble went away for about 6 weeks but has reappeared worse than ever. There is never any warning except that it happens after warm up and mostly after a hill climb or two at 70 mph. It is definately temperature sensitive. The engine is always at normal operating temp when it starts. I have gauges on the boost, exhaust temperature and lift pump pressure. All are ok on their respective readings when it happens. I'm starting to really dislike DODGE and their calloused attitude about this well documented, common and dangerous problem.There should have been a recall. They know what causes this. I wish I could find out. Any advice??

 

Sounds like TPS and/or APPS. It's a fairly expensive fix, but it stopped mine from stuttering.

Have you done the reset procedure? Do a search here and you can find simple step-by-step instructions.

 

I've reset it several times to no avail. (disconnect the battery negs. , let it sit 30 to 45 minutes with the key on, turn the key off re-connect the bateries, turn the key on and slowly depress the foot feed to the floor and slowly release it) If that is not the correct way to do it please advise me. The computor codes are never consistent. I am working with Diesel Power of Waco where I get my parts at much lower cost than the Dodge house. When the APPS was replaced by another shop in June it cost me around $400 labor included. I do my own work whenever I can because chasing an intermittent problem like this becomes a "shop swap and pop" at my expense otherwise.

 

I CHECKED AT MY DEALER IN BENTON ARKANSAS AND THEY WANTED $442 FOR THE TPS WHERE CAN I GET IT CHEAPER.

 

I have checked from a Cummins dealer in SW Missouri and you can't buy just the TPS. You have to buy the whole - "Control Gear Shift, " (Cummins # 3970084) and it's $336.59. I am not sure what it includes though. I am going to try and get a parts breakdown of it. Is it possible that the APPS could be included?

I tried the reset last night to no avail, and I cleaned all of the grounds both on the batery and to the truck frame.

 

My '99 acted the exact same way. Turned out that the MAP sensor was bad. Just a thought, and at around $50 from a Cummins house, might be cheap enough to give a shot. It sure fixed mine.

 

How were they able to determine that it was the MAP sensor?

 

Thanks for the input. I have been suspicious of the MAP for a while and just priced one at the Cummins dealer for $48.75. I will pick it up in the morning and try it for a cure. Hope it works. I'll keep you posted on the outcome.

 

I just talked to a diesel tech. and he thinks that my injector pump is causing all of the problems that I'm having and that it can cause the the TPS code to show and that my MAP sensor is probably not part of the problem. So now I go from a $400 part to $1500 or more for the injector and lift pumps. I don't really know what to think. I should have given up 7 years of college for diesel mechanics school!!

 

I think after many phone calls - that I am going to replace the lift pump and go from there. The next step is the injector pump. Any advice???

 

for the last 6 months, my 98.5 dually has been randomly hitting an acceleration flat spot (no power, but no loss of power either) similar to that mentioned above. for me it happens when i try to accelerate after a few minutes of cruising in 5th gear at 1200-1300 rpm. pressing the clutch in and out lets the engine kick in.

i've spent ages researching this and the best place to start seems to be the fuel pump. so i'll install a gauge and see if a new pump is needed.

 

For me, it was a combination of "process of elimination", and "lack of funds". When my '99 started acting as described, I immediately thought it was fuel related (I don't have a fuel pressure gauge ), so I changed the filter. No difference, so then I assumed it was the lift pump. My lift pump was the original one, with over 200,000 miles on it. So, I changed the lift pump, rigged up a handheld pressure gauge (yes, I am stupid, and did not check the original before I replaced it), and checked the pressure on the replacement lift pump. Had good pressure, but the truck still wasn't fixed. I came to this board for help, and several people indicated it might be the IAT sensor, so I pulled and cleaned that, but no joy. I also replaced the CPS. Finally several people mentioned that, even though there were no codes thrown, it could be the MAP sensor. Turns out they were right on the money.

This board has saved me a ton of cash that would have otherwise gone to the dealer for diagnosis/repair. Excellent place to learn about our trucks, and particularly the engine.

 

My replacement MAP got backordered so I will get it this evening and try that for a solution. I to have been told that the injector pump is the probable cause but I am very skepticle about that diagnosis. Yes, I believe that the inj. pump is the reason for the power loss but I feel that it is being told by the ECM to shut down. This engine runs too good when it runs which is most of the time. I believe that a worn out pump won't fix itself for periods of good running time and then crap out for shorter periods only to run good again later. I might be wrong but 30 years of industrial maintenance engineering tells me to dig deeper into the problem than the obvious surface solutions. I'm always open for suggestions. Humbleness is my specialty.

 

I have a 98.5 that has also had this problem. It has always run bad when cold but when it warmed up, it ran fine. Bought a used ECM and it started going to idle at cruise speed. It might do it several times in just a mile or so or it might run 600 miles and never act up. Put the old ECM back on and it doesn't do it any more. The problem now is it has to run about a mile before it has normal power. This has been happening for about 2 years. The truck has 272,000 miles and I was thinking about replacing the VP44 and ECM. Sure hope someone finds a cure.