Engine Stutter Mystery

[Mose705]

Hey everyone, 

New member here but long time reader, I recently bought another dually (lucky number 3) to replace my 2000 24v.

Sorry in advance for the long post, just want to give all info

Amazing truck and very well built, however.... i bought it and the abs module was unplugged, never really considered this a problem ( not a fan of abs) but im sure you all know that the speedodoesnt work without it and is a requirement for certification in Ontario. So i plugg the moduleback in, everything is fine...until it isnt, the truck began to stutter at various rpm (changed ECT Sensor) once i did that the "Stutter" was only in 6th gear at 2100rpm (had a comp box and a CAT 95gph LP at the time) Unplug the Module and everything is right as rain and has excellent power. Decided to switch over to a fass (in case of contamination) and also switched to the Juice w/Attitude ( just a personal preference... i love the dummy settings because im a dummy) Changed the MAP at this point because i had no electronic reading for boost. Plugged back in at this point and test drove it for about 5 minutes before the issue came back. I am stumped on this one gentlemen, I sure hope someone has encountered this issue before.

 

Thank you in advanced.

Chad

Pressure @ VP >16psi....Boost Max 47psi...EGT never exceed 1200F*

 

 

 

2002 Dodge Ram 3500 Sport (Daily/Plow Truck)

-Edge Juice w/attitude (unlocked plus EGT on manifold)

-BD Super B Special

-BD SS Manifold

-BD Intake Horn

-Hamilton 100lb Valve Spring 

-Hamilton Pushrods

-ARP 625 Headstuds

-Southbend 3250 Clutch

-Hewitt Mechanical Gauges (Fuel,EGT{After turbo},Fuel Pressure)

-Fass 150 gph LP 

-Colt Cam (Big Stick) Stage 3

-VP44 (100+ aftermarket)

[Hawkez]

Welcome to the forum and that is a great looking truck.

If you suspect an issue with your ABS you ought to have the codes ran...I know that isn't easy or free, but that may get you on the right track.  There has been discussion on here about a place in Idaho that can rebuild those ABS modules if that is what is needed.  Understanding the codes may get you pointed in the right direction.  Have you checked for regular engine codes?

[Mose705]

@Hawkez, thank for the reply and taking time to read, I ran my Edge Diagnostic (won't do ABS) and got the following codes

p0177 (water in fuel) i assume its because i removed the stock filter

p01693 (companion Fault) i assume its ABS related

p0238 (Boost Sensor High) i assume its because of the 47lbs

P0380 and P0382 (Glow Plugs 1 and 2) Doesnt bother me that they dont work, she starts amazing in temps around -35c*

p0622 (fuel Pump Circuit) old owner had molested the harness a bit and i decided to run my own wiring until i can afford a whole new harness

p0500 (speed sensor) have changed both abs sensors on the front axle and the one on the rear so im not sure about this guy

p0622 (generator field control circuit open) Dash tells me no alternator, Edge says 14.1v

My neighbor works for CAT and he has the abs reader which gave me the same codes and nothing ABS related

 

Thanks again

[Me78569]

You shouldn't have the boost code with the edge installed. The ecm should never seen more than ~16psi due to the edge boost fooling.  

 

1693 is just a code saying the ecm or pcm has more codes.

have you verified that the grids are working?  you truck should not start that cold without the grids so something weird is going on there.

p500 check the wiring junction above the drivers front wheel.  all the wires for the bed of the truck run through that plug.  easy to get a bad plug there.  Does your speedo work?  Are you spinning your tires a lot?

 

Strange that the edge see's volts ( I don't know if the edge has it's own volt meter or if it reads it from the ecm)  I would guess you have a pcm/ecm/ccd network issue.  

 

Very random codes to have.  maybe a bad ECM? or failing ecm?  but I wouldn't throw money at it yet.

[Hawkez]

You said this is your 3rd Ram, can you use the ECM out of any of those for troubleshooting?

[Mose705]

@Me78569, Thanks for the interest in this issue, i have the same truck but non HO and a 2000 reg cab with the same edge setup, and have never seen anything to do with boost codes, so ill look into that right away.I havent checked the grids yet as i will just swap the out with my 2000 and see what changes there ( i dont have much for electronic testing equipment) as for the speedo, it works when the abs module is plugged in but not when unplugged and i rarely spin the tires but it does happen when i sneak onto the highway in a hurry (45lbs gets her excited) I would assume the edge has its own voltmeter seeing as how it has a positive and negative terminal to the battery. I hope it isnt the ECM haha but if thats the case i will take some time without a speedo and start saving

@Hawkez that will be my next step im thinking, also i could be wrong here but i always assumed that they are vin locked?

Also i just remember the other day i msg'd the old owner to see if he ever ran a boost fooler other than edge and he said yes, but it fried the ecm ( leads me to belive it is a new one)

[Hawkez]

I don't know about them being VIN locked, but I am sure someone on here will chime in with the correct answer.

[dripley]

Welcome and that is great looking truck. I dont think the ECM's are vin locked. Too may people have swapped them to do the same test. It does need to be from a very similar truck to work, year, tranny, and such.The closer to the same the better. They do need a vin # for programming a blank ECM. I agree the grids have to be working to start that cold. Mine are disconnected and when gets to about 20*f mine does not enjoy starting. No way mine would start at -35* C or F. I have no codes for them being disconnected either. Maybe some other issue with them? I have set a n over boost once with my comp, cleared it and it never came back, not sure why. You could try clearing the codes and see what comes back to be sure some are not old.

Again welcome.

[Mose705]

@dripley thanks for the response, I should clarify that I plug in my trucks regardless of temp during the winter since the weather is so unpredictable here. when I start my truck in the morning I don't even bother with "wait to start". I have cleared the codes twice today and sadly they just come back. as for the ecm, for some reason it slipped my mind that while I do have the same truck, it is a non HO and automatic not to mention how the tiniest things are different on the 02's haha

[dripley]

1 hour ago, Mose705 said:

@dripley thanks for the response, I should clarify that I plug in my trucks regardless of temp during the winter since the weather is so unpredictable here. when I start my truck in the morning I don't even bother with "wait to start". I have cleared the codes twice today and sadly they just come back. as for the ecm, for some reason it slipped my mind that while I do have the same truck, it is a non HO and automatic not to mention how the tiniest things are different on the 02's haha

If I pug mine in it has started fine down in the single digits without the grids. We dont see temps that low around my neck of woods very often. Even with the temps that low my water temp shows about 79*F on start. The old Cummins has no problem with that.

Mike has had some issues with speed sensor installs, mainly the front ones and I have read in the past of others having issues with them not functioning properly. I think it has to do with the distance the are installed from the tone ring. Not sure how to over come that. That could be part of the problem.

I am not sure the HO part will make a difference but the auto part might. It would be worth a try and it dont cost a dime. The worst  it would do is have a hissy fit looking for input from the auto. Have to see if others more enlightened have anything to add to that.

I look at my 02 as the culmination of many years of perfecting a beautiful piece of highly performing, engineered marvel. Then I wake up and look at my to do list for the truck.

[Mose705]

interesting, I'll look into all that today for sure! as for the cold start, it's -21*c this morning and once I went out my block temp was 52*f and performed a cold start (block heater plugged in) my 2000 wouldn't even dream of it haha I would have cycled 6 times before an attemp haha but the 00 wouldn't even consider running if she wasn't plugged in regardless of how many cycles 

[Mopar1973Man]

14 hours ago, dripley said:

Mike has had some issues with speed sensor installs, mainly the front ones and I have read in the past of others having issues with them not functioning properly. I think it has to do with the distance the are installed from the tone ring. Not sure how to over come that. That could be part of the problem.

I'm still having issues with the front sensors. I know for sure the sensors are good and the ABS module is good. I'm going to go after the unit bearings next.

5 minutes ago, Mose705 said:

interesting, I'll look into all that today for sure! as for the cold start, it's -21*c this morning and once I went out my block temp was 52*f and performed a cold start

LOL. I lost my block heater cord a few winters back and start bone cold at -25*F (-31*C). Just cycle the grid heater twice and start it up.

[Mose705]

57 minutes ago, Mopar1973Man said:

I'm still having issues with the front sensors. I know for sure the sensors are good and the ABS module is good. I'm going to go after the unit bearings next.

LOL. I lost my block heater cord a few winters back and start bone cold at -25*F (-31*C). Just cycle the grid heater twice and start it up.

Thank for taking a peek, have you ever seen anything like this where once the modulee is unplugged everything is fine? 

I'll take a cold start on any of my 24v's over my 6.7 haha once she's going she's good though!

[Mopar1973Man]

Mine is the same way ABS wise as soon as the module is unplugged the normal hydraulic brakes return. So the problem is there is no way for a end user to verify the data being sent to the ABS module and what it's attempting to do. My problem is I've replace 4 sets of ABS sensors now with no change. I've rebuilt the ABS module and no change. I've swapped a module from a 2000 Dodge truck still no change. But it does a weird pull and jerking of the front brakes. The only thing left is the possiblty that the tone ring is slipping or spinning free in the hub. I've not checked for that yet.

[Mose705]

17 minutes ago, Mopar1973Man said:

Mine is the same way ABS wise as soon as the module is unplugged the normal hydraulic brakes return. So the problem is there is no way for a end user to verify the data being sent to the ABS module and what it's attempting to do. My problem is I've replace 4 sets of ABS sensors now with no change. I've rebuilt the ABS module and no change. I've swapped a module from a 2000 Dodge truck still no change. But it does a weird pull and jerking of the front brakes. The only thing left is the possiblty that the tone ring is slipping or spinning free in the hub. I've not checked for that yet.

Hmmmm sounds very similar but mine feels like a defuel/speed limitation/Rev limiter but only in 6th gear while the module is plugged in now.My stutter has nothing to do with brakes unfortunetaly lol i wish it was so it could be slightly easier to diagnose

[dripley]

Ow is your fuel pressure when it starts stuttering?

[Mose705]

Sorry for the late reply, the fuel pressure doesn't budge on either gauge (mechanical or digital) still put a fass as a precaution

[Me78569]

I would really look at that map code.  

 

Does the edge read 0 psi boost at idle?  If you clear codes then just let the truck idle does the p238 code come back?  Do you have the ability to use a like data tool, such as a code reader or scan gauge?  I would check and see what the ecm is reporting for boost.

 

I think your stumble is related to that,  I am guessing your edge is not boost fooling %100 of the time and the ecm freaks when it sees high boost, and defuels.

 

I am guessing you have a short someplace on the map leads betweem the ecm and edge.

 

I would use a multimeter to test for continuity between the pins of the map plug.  If that all tests good then I would start looking for a new ECM as I would guess that the boost circuit in the ecm is burnt up.

 

 

[Mose705]

@Me78569 The edge does read 0 psi at idle, if i clear it the code only comes back after a short ride.

I can get my hands on a quality reader but i have to wait for the weekend. Im starting the think that the old owner did not realize that the edge has a boost fooling feature and then he tried to " double down" by adding a boost fooler and then fried the ecm like he had mentioned. I made the assumption that he had replaced the ecm but now i wonder if he actually has.

[Me78569]

putting another boost fooler in front of the edge shouldn't hurt anything, it would just prevent the edge from ever seeing anything about 20ish psi.

 

I am guessing that at some point in the process the wiring got managled or something causing a short.  I would still test all 3 pins on the map wiring to the ecm and ensure that you are not having any shorts between the wires.