have a 2001 2500 24 valve that every so often loses revs right down to idle speed ...if stopped and started again it will work fine for a period of time? Garage not sure what it is. It only happens if hot and stopped and started again.....Its strange and very annoying when reduces down to 20mph until you can pull over and stop and start the engine.<br><br>Has anyone had or heard of this ?

 

Maybe the APPS (Acelerator Pedal Position Sensor) (used to be called a TPS, Throttle Position Sensor)<br><br>Might want to check that out. It's right above the injection pump, it has a &quot;bulb shaped&quot; plastic cover,, remove the cover and the APPS resides in there. (The APPS cover is one of the first things you see besides the Turbo, Valve Cover, and Intake)<br><br>I don't think you can by any parts seperate, you have to buy the whole unit, but if you are under warrenty (less than 100K, and no major BOMB's) then take it in if you will to the dealer and they should be able to pop a new one on. A new APPS does not recquire a re-flash of any sort. Just some calibration.<br><br>Hope This Helps,<br>Merrick Cummings Jr

 

Before you go tearing into the APPS, you might want to try the reasonably easy reset procedure.<br><br>It can be found here, in the Tech Facts section.<br><br>https://www.dieseltruckresource.com/...p;onlynewfaq=1<br><br><br>phox<br>

 

Thanks...I will look at those...any advise you give me is a great help !<br><br>The truck was imported into the UK which unfortunatly only had a 1 year warranty......so im trying anything to avoid huge repair bills.<br><br>The garage is unsure so far as only happened a couple of times for them and dont want to keep fitting parts until it works. They poss lack the experience and resources you guys have

 

You can take a standard OBD reader from Toyota and set it to display the throttle position. Then drive until it acts up and look whether the OBD tool reads your throttle position or not. <br><br>HTH<br><br>AlpineRAM <br>

 

Thanks...I have tried Apps reset procedure but no different.... <br><br>I think thi smay become expensive.<br><br>Here is a more detailed description of the problem<br><br>In the morning from cold no problem. If I stop for say over 1 hour and then start and move away ok.....then after 1/2 mile or so the engine seems to retard and will not go above tick over - sometimes by changing down to '2' or using kickdown the engine will respond for a while but will repeat problem shortly afterwards....<br><br>Once the engine is hot again after say 10 miles there is no further major problems if you keep a constant speed ( you can sometimes feel engine start to fall back but can recover by hitting acc hard.<br><br>If it is the APPS at fault is it a Cummins or Chrysler part ? As we have a Cummins specialist in UK and may be able to help.<br><br>

 

Go to Cummins.<br><br>Sounds more and more like a APPS sensor, but it COULD be a lift pump, or VP44.<br><br>Merrick Cummings Jr

 

[quote author=tttccchhh link=board=4;threadid=14555;start=0#137599 date=1052842836]<br>Once the engine is hot again after say 10 miles there is no further major problems if you keep a constant speed ( you can sometimes feel engine start to fall back but can recover by hitting acc hard.<br>[/quote]<br><br>That is exactly what it felt like when I had a bad lp. I hope you find out what it is before it does get expensive.

 

Check the Fuel pressure coming out of the lift pump. Anything below 8 psi warrants a replacement.

 

Well, check fuel pressure, and take an OBD scanner (Almost every jap. car dealer has one) and look into the sensors. <br>Have you checked all your connectors lately ?<br><br>AlpineRAM

 

Have you found what was wrong with your truck? Curious since my truck is doing the same thing.

 

As yet no.<br><br>I have written to Dodge for advise. awaiting reply.. ( more to do with warranty ).As as far as the problem is concerned I am going to leave the truck with Cummins in the North of England when I return their nest week.....<br><br>Please let me know if you have any success. I feel I am going to have no choice other than to fit parts as Cummins advise<br><br>lets hope they are right 1st time.<br><br>

 

Well, still no luck with my truck either. I first cleaned the MAP sensor which seemed to help some. I felt confident that I was on the right track since cleaning it helped, so ordered a new one and installed. No change. I tested my lift pump yesterday figuring that had to be it. Tested good. Never could make it drop below 6 psi at full throttle. Also, gauge never dropped when the engine would loose power. Does not seem to smoke either when it looses power. ??? I am confused.

 

Could it be the IAT sensor?

 

I am still having the same power loss problem with my '99 3500. New MAP and IAT sensors did not correct the problem. Check engine light does NOT come on. Anyone have any suggestions????