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Engine stumbles


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6 minutes ago, Dieselfuture said:

So reworking injectors helped and now it's back to same thing? 

Yes, although I did not tow with it until today. This bucking happens in drive and overdrive. Kinda like lugging the engine at low speed. Most notable at 55mph, I'm running 1550ish rpm, 22% throttle, and 16° of timing. The canbus is all over the place, don't know about that. Load is around 20 to 25%.

Edited by mossyoak71
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16 minutes ago, Dieselfuture said:

Can't remember did you do ground mod and checked alternator? Fuel pressure staying above 14? So is Cummins in the Ford? Or you have 2 trucks

Alternator is fine, fuel pressure is a constant 18psi. The Cummins is in the Ford.

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Are you positive there is no codes, I'm just trying to think and it hurts lol. I feel your pain though, my truck been through similar issues and it sucks. You'd think if it was electrical, it would throw a code, that's why I suggested injectors. Mine acted like that and injectors and alternator did the trick. I never had any codes ether, was very frustrating. I would of changed the VP in a heart beat if I had the code, glad I didn't now. I'd hate for you to change it and not fix it. Now wondering if your pop is too high? But at same time I don't think so. Yes data log wold help to see what drops out. I belive you reset it as you drive and start dataloging and attempt to have problem come back as soon as you get your symptoms pull over and see if you can save the dataloging file, by exporting it.

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No codes, and just getting very disappointed. Wishing now I would have p pumped it. It's even doing this on the stock tune setting. The alternator is a Ford and it was tested ok. Engine has more grounds on it than VanCamps has pork n beans. I placed more.grounds on it as I run a linear and push alot for talking skip. Money isn't the issue, it's listening to my wife that kills me. Luv her though! 

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Mine bucked to high hell no joke with the TPS Pump Max set to 0. I was towing and trying to quickly turn off wire tap by setting it to zero, and it bucked so hard I'm surprised nothing broke/The engine didn't fall out.

 

My truck also bucked hard when lockup engaged at light throttle. Jacob thinks it's a big injectors issue. Solution is to turn fueling down to mid to low 70s at low PSI ... So when it locks the TC and I'm light on the pedal & low in the boost that solves the problem.

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1 minute ago, rogerash0 said:

Mine bucked to high hell no joke with the TPS Pump Max set to 0. I was towing and trying to quickly turn off wire tap by setting it to zero, and it bucked so hard I'm surprised nothing broke/The engine didn't fall out.

 

My truck also bucked hard when lockup engaged at light throttle. Jacob thinks it's a big injectors issue. Solution is to turn fueling down to mid to low 70s at low PSI ... So when it locks the TC and I'm light on the pedal & low in the boost that solves the problem.

I tried turning the starting point down and if I go below 82 the truck stalls. It's been raining cats and dogs here today so I haven't been out of the house to get the tune. But I know if I go that low it dies.i don't have an issue going through the gears, just a steady rpm and it does it or hammer on it from 55ish it will do it after a few seconds of reving. Almost feels like a skip.

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I would try to bump your timing up to 18 or so degrees. At 330BAR your about 3 degrees retarded, so your timing is really about 13 Degrees not 16. It maybe worth pushing it forward a few degrees to change your timing. As even my Smarty doesn't go farther then 18.25*

Questions.

 

1. Is this under boosted applications only? Does the bucking get worse as the boost goes up, or is it rpm dependent?

 

2. do you hear any mechanical timing knock?

3. Does the thumping go away if you lay off the throttle enough to kill the boost?(Like maybe a wrist pin is going south)

4. Have you considered putting in a lock up switch and testing to see if it happens in 2nd as well?

5. What are your line pressures in the transmission as well? Trying the rule out TC shudder, as my truck was bucking from the torque reversals hitting the TC as low line pressures.



I'm not entirely set on the idea that this is strictly injector related since it was happening before as well, however, I did go through this before with my older injectors as Mike can tell you, I had a load based pinging that was due to an injector that was acting up. I was able to diagnose it by fooling the truck into 3 cylinder high idle and then swapping the injectors till the thumping went away. When DAP looked at it the pintel failed on the injector.

Edited by pepsi71ocean
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46 minutes ago, pepsi71ocean said:

I would try to bump your timing up to 18 or so degrees. At 330BAR your about 3 degrees retarded, so your timing is really about 13 Degrees not 16.

no way no how

 

there is no noticable difference in timing based on pop of 330 vs pop of 310.   that 1* per 10 bar is myth.

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6 minutes ago, Me78569 said:

no way no how

 

there is no noticable difference in timing based on pop of 330 vs pop of 310.   that 1* per 10 bar is myth.

 

I'm not so sure Do you have any information to back this up?

I'm unsure since that the timing pressure curve has to go up exponentially as pressure rises. He's swinging some big injectors 250hp injectors IIRC. I'm thinking that stock maybe his injectors were 300 bar, or maybe 310. Although I believe Jkidd mentioned in a previous thread that pop pressures on 250's is about 315 BAR stock?

 

I have been wondering this, but I've had several injector shops agree with the timing bump theory. I've been told that you can get an injector to put out 100hp's worth of fuel, but you can have different internals that will make it different. But the one things that they have stated is that the time to build the pop pressure from 300 bar to 330 bar is much higher then from 280 to 300. The fluid compression is what I've been told is the major issue.

 

 

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A couple of thing

 

1. I hear no audible difference at idle between the 300 bar and the 350 bar.  I ran these back to back.  350 bar should be ~5* of timing difference.  There is a VERY audible difference in that much of a timing swing. having played with timing that much it was very apparent that there was not a big difference in overall timing at idle.

 

2. when I compare idle state between 300 and 350 bar I see only a %3 diffence in duration command to keep the same idle.  Again if there was that much delay in the fueling I would expect that duration command to be alot different to keep the same overall fuel injection the same.  

 

3. 5* of timing difference on a cold truck would result in heavy white smoke.  I know this because I did it during the trial and error of making the V2 tuning.  going from idle of 12* to idle of 7* made the truck idle terribly.  My idle with 350 bar was no different than stock bar.

 

 

 

Keep in mind that you are only thinking about the starting point of the injection event.  The actualy combustion event is what matters.  With higher pop you are moving the front and end of the injection event, I am not sure the actual combustion event changes a significant amount. the finer spray would lead to the combustion event happening sooner as well, offsetting the delay of the injector opening.

Biggest thing, is there way no real difference in how the truck ran with 350 bar vs 300 bar.  I noticed because I was doing logging and testing, but the average joe would have no idea.

 

Edited by Me78569
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On 12/3/2018 at 11:03 AM, Me78569 said:

A couple of thing

 

1. I hear no audible difference at idle between the 300 bar and the 350 bar.  I ran these back to back.  350 bar should be ~5* of timing difference.  There is a VERY audible difference in that much of a timing swing. having played with timing that much it was very apparent that there was not a big difference in overall timing at idle.

 

2. when I compare idle state between 300 and 350 bar I see only a %3 diffence in duration command to keep the same idle.  Again if there was that much delay in the fueling I would expect that duration command to be alot different to keep the same overall fuel injection the same.  

 

3. 5* of timing difference on a cold truck would result in heavy white smoke.  I know this because I did it during the trial and error of making the V2 tuning.  going from idle of 12* to idle of 7* made the truck idle terribly.  My idle with 350 bar was no different than stock bar.

 

 

 

Keep in mind that you are only thinking about the starting point of the injection event.  The actualy combustion event is what matters.  With higher pop you are moving the front and end of the injection event, I am not sure the actual combustion event changes a significant amount. the finer spray would lead to the combustion event happening sooner as well, offsetting the delay of the injector opening.

Biggest thing, is there way no real difference in how the truck ran with 350 bar vs 300 bar.  I noticed because I was doing logging and testing, but the average joe would have no idea.

 

 

This is really interesting to note. As for me the only difference I've noticed is that my S03 burns almost clean. I see very little to no smoke, Unlike before where she would roll coal constantly. This truck you need to make it roll coal, and she'll do it. The pedal is very forgiving about coal and spool up. The shifting is more firm as well.

This is is why I'm still puzzled about the effects of raised pop pressure on the truck.  I'd like to pick your brain about writing an article about raising pop pressure for the Smarty trucks. I feel like people will find that useful, especially for guys like me who still run the S03 with larger injectors.

 

 

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better atomization.  I dont think it has anything to do with timing.     

 

I noted a difference of smoke output related to fuel duration of ~6-10% 

 

IE: a truck with 330 bar pop could run %6-%10 more duration across the board without smoke compared to someone running 300 bar.  

 

 

 

I think raising pop pressure is not something you should be recommending to people.  I noticed harder starts when it was cold at 330 bar.  To the point of being dangerous if you needed to start the truck and it was cold, IE below 20*f  

 

It is also widely unknown what, if any, the long term issues of increased pop is.  i noticed a better running truck at 330 bar with the 7 x .012's but I dont recommend people do that because I have no idea what the issue might be on the system as a whole ~12 months down the road.  

 

 

 

I liked what it did for my smoke output, but I think a WAY better solution for guys having smoke control issues is to upgrade their tuning.    The S03 is not tuning for the current era.  I kinda regret ever posting anything about pop pressure, it was not my intention to suggest to people to try it, it was only because I was bored and wanted to mess with it.

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3 minutes ago, Me78569 said:

better atomization.  I dont think it has anything to do with timing.     

 

I noted a difference of smoke output related to fuel duration of ~6-10% 

 

IE: a truck with 330 bar pop could run %6-%10 more duration across the board without smoke compared to someone running 300 bar.  

 

 

 

I think raising pop pressure is not something you should be recommending to people.  I noticed harder starts when it was cold at 330 bar.  To the point of being dangerous if you needed to start the truck and it was cold, IE below 20*f  

 

It is also widely unknown what, if any, the long term issues of increased pop is.  i noticed a better running truck at 330 bar with the 7 x .012's but I dont recommend people do that because I have no idea what the issue might be on the system as a whole ~12 months down the road.  

 

 

 

I liked what it did for my smoke output, but I think a WAY better solution for guys having smoke control issues is to upgrade their tuning.    The S03 is not tuning for the current era.  I kinda regret ever posting anything about pop pressure, it was not my intention to suggest to people to try it, it was only because I was bored and wanted to mess with it.

 

Don't regret it. There's nothing much about it on the other forums.

 

I haven't seen any issues myself, but Maybe that is a mixture of fueling and commanding based on a programmer?  I haven't had any issues yet and mine fired right up without grids at 17F out.  But That maybe also because of the smarty?

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cranking as close to open loop as you can get, I doubt your truck cranks at a different duration / timing than mine did.  I doubt smarty messed with cranking fueling and timing.

 

likely has to do with with the size of the injector.  it got MUCH harder to start near that 20*f mark, also consider I am much higher in altitude.    Point being that I have had reports of this same issue from others as well, I can't suggest it to anyone knowing that it does cause starting issues in the cold.  the other member in canada that popped his own injectors ran into the same issue.  

 

It was like a light switch, just a few * difference and there was no issue, then bam issue starting.  

 

 

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3 minutes ago, Me78569 said:

cranking as close to open loop as you can get, I doubt your truck cranks at a different duration / timing than mine did.  I doubt smarty messed with cranking fueling and timing.

 

likely has to do with with the size of the injector.  it got MUCH harder to start near that 20*f mark, also consider I am much higher in altitude.    Point being that I have had reports of this same issue from others as well, I can't suggest it to anyone knowing that it does cause starting issues in the cold.  the other member in canada that popped his own injectors ran into the same issue.  

 

It was like a light switch, just a few * difference and there was no issue, then bam issue starting.  

 

 

 

See that's where I was wondering if this is related to Injector size. I do believe that popping 75's to 330 bar would post an issue, unlike my 100's or 150s per say. My truck fired right up at 17F without grids. Which has me tossed.

You are running 100's or 150's?

Edited by pepsi71ocean
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