mr-walleye

As I mention above I need help, here is the whole story Bought 05 ram as a wreck and repaired it and is on the road now Originaly the truck when reved in neutral would stay at 2000 rpm and not come down at all until the key is shut off. Had it scaned and the teck at dealership found no codes and only indication to a problem was the injector performance test ,two injectors read weak at 77% &82%. So I changed the injectors. I also finaly did an engine service and found lots of dirt and sediment in filter bowl, the filter was black with dirt Okay so now I know what hapened, it must have sucked the dirt into the cp3 when it rolled? Started truck after all the work was done and I thought I was in the clear because it reved up normaly and came right back down with no hanging or hesitation______ until it warmed-up.After it was warm it mildly hangs for a few second but comes down stuttering not smooth at all like when it is a cold start.Please give me any insite I read about the FCA and I wonder if that is part of the problem? Other than that the truck holds high idle fine,dosn't miss, smoke or hard to start.Is there only one filter on this 05 or is there a screen after cp3 pump?oh and the oil was BLACK but not over full.

mr-walleye

I guess I am the only one to have this happen to? Am going to try cap all injectors one at a time to see if that is all it is. Priced local injectors $520ish new cdn price.

RCW

The 05 is drive by wire, so the source of the problem is most likely the variable switch that is connected to the throttle. If that switch or the throttle linkage itself is sticky it will not generate a code unless the throttle angle is greater or lesser than the ECM believes it should be for the engine rpm and fuel rail pressure.

There are no screens after the injection pump. It should not have sucked any dirt into the injection pump unless the filter itself failed and allowed dirt to bypass the element. But, if the pump were failing you would have seen significant out of tolerance pressure related codes during the scan.

There is one other thing, but the tech would have informed you of that if he knew it was a rebuild/salvage vehicle. Once you completely disassemble the wiring harness on any of the common rail engines it is necessary to have the computer reflashed. So, after the rebuild it should have been taken in and had the reflash done to bring everything into sync.

mr-walleye

Thank You RCW for the reply but the truck was running like this in its original form all I did was change sheet metal. The truck as never thrown codes,and as for the peadel switch the tech seemed to think it was all right.Now the fuel filter I am sure was aftermarket so I guess it was 10micron,and it was BLACK and pluged. How much dirt could that have let in once it was pluged? I capped #1&#5 injectors one at a time and #5 didn't make much change,but#1 made a fair improvement.I just don't want to throw $2200 more for four more new injectors.I gotta get it fixed, I need the truck in two weeks!

jcarrillo

I had a similar problem with an 05 at work. The truck wouldn't throttle all the way up. I ran a diagnostics test on it with a snap-on modus and it turned out to be a FCA.It pulled a code but I don't remember what it was. From what I've read on here though, Injectors do that when the are sticking too. My '05 did that when I had an injector go out. It knocked and smoked very bad though. The thing about "go out" is there are many ways that can happen. There are elecrical failures and mechanical failures. In my case, the pental stuck open and the modus couldn't detect that. It will only detect electrical failures. I am not sure how the dealers diagnostic computer works as I have never been to the dealer for diagnostic testing but if your in a hurry and don't want to spend money and be wrong. The FCA is not an expensive part and is very easy to replace. If it was me I would try that first. If it doesn't fix it I would go after that #1 injector. I bought two injectors for mine (thats all my budget at the time would allow) when I had problems and I started switching them out until I found it. It took alot of time to do that though. Before it was all said and done I ended up disconnecting the exhaust manifold to see which port was smoking to find the culprit which is what I should have done to start with. I am not sure if all this info will help you since our problems are a little different. After I replaced two injectors on my truck I found out that you can buy a whole set of nozzles for the price of two injectors. I have rebuilt mechanical injectors in the past and you have to shim them to get the right popoff pressure which requires information and test equipment. I was skeptical at first, but alot of people have changed theirs on here without any problems with rough idles or other problems so if I had to change more that two injectors again due to mechanical failure in the injector I would rather get the nozzles than one or two whole injectors. I would also start with a two micron filter and see what it does after that. Keep plenty on hand with you. If the tank looks anything like that filter you will change several before it cleans up. You will know when to change them, it will lose alot of power. Be sure not to run it to long in that condition either as it will contibute to the failure of your lift pump. Another long story. I am sorry this post is so long but I wanted to give you the benifit of being able to use my experiences to help solve your problem. If you don't get it figured out with this info, pm me again and I'll give you my phone number and you can call me and we'll discuss it further. Joseph

mr-walleye

Thanks for all the advice and trouble shooting. I finaly got fed-up and ordered and changed the remaining four injectors today. I crossed my fingers when I first started it and I was very very happy to finally hear it run right!As soon as I took out injector #1 all the dirt that had gone through the injector was visable, and it was a lot!! It took the whole day because I wanted to remove all lines down stream of the filter and clean them all, including the rail. This problem just goes to show no two trucks are alike and injectors can fail in many weired ways. There is only one slight thing that still kinda bugs me and it is a very very slight shake like a miss at idle only,not under load at speed or, off idle. Maybe it is normal as I am used to the 12v.Thanks for looking and it is all better now ,lets ride

Hodges4x4CTD

I had the same stuttering when coming down from 2000rpm. Put in a fass150 no help, computer said injectors, changed all six, no help, swapped fca problem fixed. could've been out $150 instead of a buch!
the fca can't be diagnosed while sitting even with a scan tool, has to be drivin with hooked up

jaybone

I am having the same issues with hanging throttle, where did you find FCA for 150.00. I am ready to start throwing parts at it and figure start on the low end first and injectors last.

Is there any way to isloate the injectors besides capping off and see if the problems quits?

Hodges4x4CTD

if you know a shop that has the scan tool, have them hook it up and drive the truck to watch fuel pressure @ the rail. sitting still it wont fluctuate as much and the computer will show a few bad injectors during the injector kill test.
Find a cummins shop, way cheaper than dealer price of $209