Engine/Transmission (1998.5 - 2002) Having a studdering problem out of my 02

[krazyquad]

Im having some trouble trying to figure out what is wrong with my truck and was wondering if anybody has had this problem or may have any ideas. First the truck has a lopy idle to it kinda like a miss and second when you are accelerating kinda hard it shutters. Ive already tried taking the edge off and ive tried my buddys edge box and didnt make a differnece and just put new RV275s, cam sensor, & a AirDog on it. Its an 02 6speed it has a edge with attitude and a couple of others things but should make a differnce.

 

[Sticks]

Do the key [ignition] "On-Off" procedure and see if there are any codes, report back.

Sounds like a fuel pressure issue, and probably a VP44 going Tango Uniform

 

[mhenon]

I agree the VP44 might be going south. Sounds just like mine when it went. Check for codes as suggested and let us know what you get.

 

[krazyquad]

I checked for codes using both a code reader and with the key switch trick and it shows nothing. Also my truck doesnt feel like it has losted power besides when it studders, no white smoke, and no long starts.

 

[mweiman]

Do you have a fuel pressure guage, If not try to get one and report back. Did the stutter start right after replacing the injectors?

Matt

 

[krazyquad]

Shuttering has been going on for the past 2 months I guess and is getting worst as in happening more often but I do have a pressure gauge its on the edge and the injectors I put in 2 weeks ago becasue I thought maybe they were the problem but it hasnt fixed it

 

[BIGNASTY]

a speech impediment on a truck ?

 

[cerberusiam]

a speech impediment on a truck ?

That would be a STUTTER I believe. Never had a diesel talk like that so am totally lost.



Studder?? Is that REALLY a word???? :-laf



A SHUDDER on the other hand I am familiar with. :{

 

[Sticks]

Air in the fuel or low pressure. What does the gauge read?

 

[krazyquad]

The Fuel pressure is no lower then 15 and no higher then 18 and yea shudder works to or bucking

 

[Sticks]

Unless something is binding up in your drivetrain...

Do a rev test.

Engine at operating temperature.
Transmission in Neutral or Park, parking brake on.
From idle, fully depress the throttle for a few seconds and watch the tack. It should travel evenly and smoothly to redline and hold (You won't hurt it, Cummins calls this "High Idle").

IF it hesitates, shudders, studders, coughs etc, you have a problem with your fuel system, or intake (check your air filter & turbo lately?). Possibly valves out of adjustment but you'd hear that at idle as well as a regular miss (delivery valve on the pump or bad injector).

Repeat, this time watching your passenger mirror and watch for smoke. You should see maybe a little puff of black then clean.

Black smoke - not completely burned fuel
White smoke - unburned fuel, water, air in fuel
Blue smoke - oil

Repeat again, this time slowly increase the RPM and see if there is a particular range where it is really bad and stays bad.

If you are getting white smoke at idle or slightly above idle, start cracking the injection lines and see if there is one or more that either does not make a difference to the idle or makes very little difference. Check them all. A studder, shudder, ect. that is not erratic is a bad thing and you need to find the source ASAP before you roast a cylinder.

 

[krazyquad]

Thanks for all the good info. I have tired that the other day but it was 3 times and all the way to the floor, but i did notice when i did it to about 2500 it was jumpy and not smooth and i didnt look at the smoke. But i do plan on trying this one day this week. I am sure its not an injector because I have replaced them 2 weeks ago with a set from injustrial injection and my old ones still had the same problem. Except now that they are higher hp injectors it does it more often because the higher the edge setting the more often it happens. So im pretty sure its the VP44 or blue chip says it maybe my APPS senor.

 

[Sticks]

APPS... forgot about that one. Only problems I ever encountered with that was issues always at the same RPM until it went Tango Uniform at a stoplight.

Fought it for 3 years, no codes until it died. Even the dealer when handed proof of erratic APPS readings on a graph (scanner) would not do anything without a code present.

 

[HBarlow]

Shudders, stutters, shutters, shooters, shouters?, hell, I'm confused. What was the problem again?

 

[Sticks]

Shudders, stutters, shutters, shooters, shouters?, hell, I'm confused. What was the problem again?

Truck aint runnin' right.

 

[Diesel Gunner]

Damn, you guys are funny!



Love the info though.

 

[BIGNASTY]

a speech impediment on a truck ?

Sorry I see an opportunity I just have to take it. It's my nature :-laf

 

[krazyquad]

Yea im going to try that APPS sensor and I also saw something on another forum to check out my fuel pressure sensor becasue ive got the one right at the vp44 so im going to take it off and run it to make sure its not leaking air in. But thanks so far with the ideas Sticks ill be sure to give you guys an update this weekend when I try a few different things.

 

[krazyquad]

I might try and upload a video of my rpms when i accelerate and maybe some sound if you can hear it good enough but otherwise thats for all the help so far maybe it will be something easy like the the APPS sensor that would be nice

 

[bromano676]

APPS, I fought the same problem on my truck while I was on vacation. I got stuck paying the ******* $800 for an in tank fuel pump. Then I spent $1300 for some trouble shooting, fuel leaks, injector testing and installation of the RV's. some of the money was worth it. The injectors paid for themselves in fuel mileage.



But on the way home the bucking, shuttering, studdering happened again. I managed to make it 700 miles with the cruise control on. Then when I took it out of cruise I could not get the RPM to drop lower then 1300. snap the pedal a few times down it came. back on the highway, and all was good with the cruise on. get off and it was stuck at 1300.



Then Dead Pedal. CEL. The rest is history. I made it home and ordered a TIMBO APPS. NO Problems since then. The really agravating part is that The APPS that gave me trouble on that trip was only 1 year old.