Engine/Transmission (1998.5 - 2002) rough idle

[mgoncalves]

Ever since I did my injectors my truck has one weird habit that I'm not sure if it's normal. At idle with a slight load (letting clutch out or idling through parking lot) the engine sounds like it is missing just a little. Not like loose injector line missing but almost like a lope. It is worse (or better) with the comp cranked up. The pattern reminds of me of my old powerstroke when in similar conditions.



Now, to confuse things even more. Last weekend, we went to North Dakota for a wedding. My buddy's father in law has a 94 Cummins and was pretty interested in my truck and it's mods. I took him for a spin and really got into it hard and had to let off sharply because of a light, when I hit the clutch the engine went into this weird idle even though there was no load on it. I tapped the pedal and it caught back up to itself. There are no codes and no problems otherwise.



Is this a problem, or is it normal. My truck has never idled very smooth and I'm thinking maybe the injectors are exaggerating the way it was before. At least that's what I'm hoping.



Any ideas?



Matt

 

[Ncostello]

Mine does the same thing and its not normal. Cummins shop showed mine was not fueling equally to two cylinders during a computer test run. They figured I had two bad injectors. So I installed 275's and it didn't help. One more test revealed two cyls were again not fueling properly... but two different ones this time. They said it had to be the VP. The truck had a dead LP when I bought it and I dont know for how long. I've since fixed that problem but not the VP. They had no way of testing the VP then... but they now have a stand and training but no software to run it. Bosch hasn't exactly been quick with giving that out.



So I found a used (10,000mile) VP pump for $400 and am waiting till I get a little time to take it down. I wanted to test my new pump first which is another reason why I've been waiting but the shop has no real date on when they'll actually be able to run them.



I've check or replaced alot of sensors etc with no luck. I also checked every possible connector and used dielectric compound on them. Has to be the VP on mine so I need to get around and install it.

 

[jrandol]

Originally posted by mgoncalves

Ever since I did my injectors my truck has one weird habit that I'm not sure if it's normal. At idle with a slight load (letting clutch out or idling through parking lot) the engine sounds like it is missing just a little. Not like loose injector line missing but almost like a lope. It is worse (or better) with the comp cranked up. The pattern reminds of me of my old powerstroke when in similar conditions.



Now, to confuse things even more. Last weekend, we went to North Dakota for a wedding. My buddy's father in law has a 94 Cummins and was pretty interested in my truck and it's mods. I took him for a spin and really got into it hard and had to let off sharply because of a light, when I hit the clutch the engine went into this weird idle even though there was no load on it. I tapped the pedal and it caught back up to itself. There are no codes and no problems otherwise.



Is this a problem, or is it normal. My truck has never idled very smooth and I'm thinking maybe the injectors are exaggerating the way it was before. At least that's what I'm hoping.



Any ideas?



Matt

Hey Matt, can you hear that Hot Rod Pump calling your name???? Shh... ... listen closely, "matt, buy me----matt buy me"



Just kidding man! Maybe we should pull those showerheads and flow test em?



Jeff

 

[Sticks]

Re: Re: rough idle

Originally posted by jrandol

Hey Matt, can you hear that Hot Rod Pump calling your name???? Shh... ... listen closely, "matt, buy me----matt buy me"





Jeff

That's mean Jeff



Get a hold of Mike Lockner. At the March wrench day, when he put the stage threes in his, he had that rough idle and lope also. He cured it, I just don't know how.



Don't go breakin' that truck before I get a chance to take 'er for a spin!

 

[mgoncalves]

Jeff, that's not funny





Sticks, I remember Mikes truck that day, I believe it was just a loose injector line.





I think since it didn't do this before the injectors, I'm going to pull them and have them checked out. That way I know I'm not scoring a cylinder or running weak on one.



Matt

 

[Agades]

mgotcalves,

its not normal but I dont think its your pump



I have the same problem along with other problems (stumble)

and have already tried the pump with no positive results



the only thing I have not replaced on my truck is the ECM ,engine, transmission, axles, driveshaft and the speed sensor on the rear axle





I think its something that the 01. 5 - 02 ecm is causing

for some reason some of these ecms cant regulate the rpms right when using a fueling box (any fueling box) (ive tried 3 diff brands)

and my problems always come back as soon as I hook up the fuel wire and dont always dissapear as soon as I unhook the wire



I usually have to unhook the batteries for it to go away

but always comes back as soon as the happy wire is installed



its like a over compensating governor



my brothers 01. 5 does the same thing

also 01. 5 is when dodge decided to get rid of the crank shaft sensor (dont know if that has anything to do with it but its a theory)



At one time Marco told me to watch the load % on a scan tool

I havent done that but I think he may be on to something



Marco , if your out there, a little more info would be much appreciated

 

[Agades]

mgotcalves,

its not normal but I dont think its your pump



I have the same problem along with other problems (stumble)

and have already tried the pump with no positive results



the only thing I have not replaced on my truck is the ECM ,engine, transmission, axles, driveshaft and the speed sensor on the rear axle





I think its something that the 01. 5 - 02 ecm is causing

for some reason some of these ecms cant regulate the rpms right when using a fueling box (any fueling box) (ive tried 3 diff brands)

and my problems always come back as soon as I hook up the fuel wire and dont always dissapear as soon as I unhook the wire



I usually have to unhook the batteries for it to go away

but always comes back as soon as the happy wire is installed



its like a over compensating governor



my brothers 01. 5 does the same thing

also 01. 5 is when dodge decided to get rid of the crank shaft sensor (dont know if that has anything to do with it but its a theory)



At one time Marco told me to watch the load % on a scan tool

I havent done that but I think he may be on to something



Marco , if your out there, a little more info would be much appreciated

 

[Agades]

mgotcalves,

its not normal but I dont think its your pump



I have the same problem along with other problems (stumble)

and have already tried the pump with no positive results



the only thing I have not replaced on my truck is the ECM ,engine, transmission, axles, driveshaft and the speed sensor on the rear axle





I think its something that the 01. 5 - 02 ecm is causing

for some reason some of these ecms cant regulate the rpms right when using a fueling box (any fueling box) (ive tried 3 diff brands)

and my problems always come back as soon as I hook up the fuel wire and dont always dissapear as soon as I unhook the wire



I usually have to unhook the batteries for it to go away

but always comes back as soon as the happy wire is installed



its like a over compensating governor



my brothers 01. 5 does the same thing

also 01. 5 is when dodge decided to get rid of the crank shaft sensor (dont know if that has anything to do with it but its a theory)



At one time Marco told me to watch the load % on a scan tool

I havent done that but I think he may be on to something



Marco , if your out there, a little more info would be much appreciated