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Idle variation, unknown cause

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Old Oct 6, 2016 | 09:57 AM
  #61  
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Originally Posted by Rikster-7700
Have you looked into ForScan? It is free and does most of what AE can do, the only thing you will need to buy (I am assuming you have a laptop to run AE?) would be a OBD II to USB adapter?
I think Forscan gives the best performance with a bluetooth OBD II and Windows laptop if you want to make changes to any programming.
 
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Old Oct 6, 2016 | 10:06 AM
  #62  
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In order to analyze the alternator concern, why not just disconnect the alternator? The truck will run fine on 12 volts out of the batteries long enough to determine if the alt is causing a surge. I personally doubt that it is but the catastrophic carnage of the Craftsman would indicate otherwise. I wound up here with an occasional errant starting and power change problem coupled with check engine light twice in the past 2 weeks. I suspect it is time for another cam position sensor but was looking for behavior clues before the dreaded full stop. As I recall the last one failed after behaving like air in the fuel such as you are describing. Was the ignition on when this occurred? Just a thought.
 
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Old Oct 6, 2016 | 01:22 PM
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Originally Posted by Rasalas
In order to analyze the alternator concern, why not just disconnect the alternator? The truck will run fine on 12 volts out of the batteries long enough to determine if the alt is causing a surge. I personally doubt that it is but the catastrophic carnage of the Craftsman would indicate otherwise. I wound up here with an occasional errant starting and power change problem coupled with check engine light twice in the past 2 weeks. I suspect it is time for another cam position sensor but was looking for behavior clues before the dreaded full stop. As I recall the last one failed after behaving like air in the fuel such as you are describing. Was the ignition on when this occurred? Just a thought.
The ignition was not on when this happened. I ran whatever cps that they installed with the recall for I don't know how many years. I am currently running the blue one from Clay. I have changed that in the last year to year and a half. I have heard of the blue ones going out more regularly, hopefully when I get a data run later today we will see if that is possibly causing issues as well.
 
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Old Oct 6, 2016 | 09:21 PM
  #64  
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Originally Posted by Rasalas
I think Forscan gives the best performance with a bluetooth OBD II and Windows laptop if you want to make changes to any programming.
Why is that? The data transfer speeds are higher with USB? Not knocking what you are saying, merely looking for another perspective.....
 
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Old Oct 9, 2016 | 06:58 AM
  #65  
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Originally Posted by Rikster-7700
Why is that? The data transfer speeds are higher with USB? Not knocking what you are saying, merely looking for another perspective.....
That is just what I have read over in the 2017 Super Duty threads regrading programming changes. Karl4Cat has used the system on a Macbook by booting into windows. Some who tried the wired system could read the output but not change any parameters until upgrading to the OBD reader with BlueTooth. Much of the information came over from the F150 side as well. The Android phone will read but is not capable of changes either.
https://www.amazon.com/dp/B006NZTZLQ...I1YSTMJRV8GJJU
 
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Old Oct 10, 2016 | 01:22 PM
  #66  
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Graph

Okay, here is your graph, zoomed it with RPM X10 to show the fluctuation

10 to show the up and down.


FIPW missing, RPM x10
 
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Old Oct 10, 2016 | 01:42 PM
  #67  
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Here's doing another run now. If FIPW is not moving, then I'm thinking CPS?

Unless the fuel delivery (Hutch mod needed) is sputtering the idle?
 
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Old Oct 10, 2016 | 09:29 PM
  #68  
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Graphs from your latest run

RPM X10, FIPW X10 to move up into the graph








The ICP is rock steady, FIPW only fluctuates minor.
 
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Old Oct 11, 2016 | 06:42 AM
  #69  
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I saw a signal flare, so I dropped by to see what's up.

I haven't read the whole thread, but I'll respond to what I glanced at:

We can't read a thread on communications in the 2017 forum and compare it with our trucks that were engineered on PCs with Windows '95.

The OBDLink MX or LX OBDII adapters are faster than we will ever need - and those are wireless (BT and WiFi). My AE USB interface I bought in 2010 is nowhere near as fast as my OBDLink MX Bluetooth, so we can't say one is faster than the other by default. The choke point is the electronics on the truck - that J1850 PWM protocol. Think back to '98 when they first manufactured the Superduty - high speed internet wasn't around, people were using modems with 56K baud (slightly faster than J1850 PWM at 43K baud), and AOL was the heavy hitter for getting online or email.

As for the variation on idle - I haven't seen one graph that focuses on IPR in high resolution yet. That's usually the bugger - it should be rock-solid when all is well. Is the fuel filter black?
 
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Old Oct 11, 2016 | 07:39 AM
  #70  
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Good to see you. Thanks, Rich

Here's the same graph with IPR x100 to show/exaggerate the IPR.




Does that help?

OP reports Blue/White smoke when starting, up to 30 secs. No black smoke. Glowplugs and UVCH replaced in recent years.

I listened to a cold start and it failed to start the first attempt and cranking about 15secs, but we had the key on (reading AE) for a while first and that means the fuel pump would have been off (I always wonder about what happens when we let our GPs on for a while but the pump shuts off- does that extend startup times?)

When it did start on the second attempt, it started and seemed to run okay, not stumbling.

I would point to GPs, but that doesn't answer the stumbling idle. If it was the CPS, I'd expect the RPM values to be dropping out?

He did have a historical code P1670. We cleared it before the runs, but haven't checked if it or anything else comes back yet. Think a KOER test would be helpful? Doesn't that check the IDM?

Seth is gathering stuff for the Hutch mod, which should be done regardless, has the Racor on order.

Rotella T6 5w-40 Synthetic oil.

We went through a lot of Q&A and stuff on the phone. I think I hit the pertinent items. Seth, did I miss or mix anything up?
 
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Old Oct 11, 2016 | 08:19 AM
  #71  
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The fuel filter is more like grey. It used to be black but after doing o rings last fall I think that has changed.

New glowplugs and Stancor relay last fall also.

I think you hit most of everything. If anybody has any questions ask away.

Thanks to everyone for there help.
 
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Old Oct 12, 2016 | 08:16 AM
  #72  
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Looking at the graph, one would need to know the normal values to decipher it. ICP would be 500 PSI at idle, your scale shows 7000 PSI or 85 PSI. I'm not trying to criticize or anything like that, my friend - I just feel the need to have good information if a reader is going to follow along and learn this stuff. The highest scale we will ever need on anything for the truck is 3500. The RPMs never top that, the ICP never tops that, the Fuel Injector Pulse Width should never top that in microseconds while running, the TC slip can't top that, and I'm almost certain I'm over looking a PID - but 3500 is the absolute scale limit we will never need to cross. When I want to see a fluctuation amplified, I squeeze the range. To explain - say my idle has a wild fluctuation at 700 RPM, I could set the scale minimum at 600 and the max at 800. That amplifies the fluctuation about 17-18 times.

If I divide the ICP by 10, I get 500 PSI - which is perfectly normal for idle with a warm engine.

The IPR would normally be somewhere in the neighborhood of 8% to 11% at idle (graph shows 10 times normal), with a lot of factors (like oil type, condition of HPOP, condition of injectors, etc...). "Most common" IPR is 9-10% at 500 PSI ICP. It's remotely possible the ICP is reading a tiny bit higher than actual, but all I suggest there is inspect and clean the ICP sensor connector. How does it start if you unplug the ICP sensor connector?

When I do a long charge on the GPs, the fuel pump cycles off - but the engine still cranks right up within the allotted 2 seconds without recycling the key.

Long cranks are frequently caused by the HPOP reservoir check valve leaking back (located on the block under the reservoir), wrong ICP values, bad injector O-rings, or very tired injectors. Synthetic oil helps with tired injectors, if it's of the tired injector variety. You can always pop the top and adjust your clearance on the injectors to eke out a little more life from them.

Seth, I'm sorry I haven't joined in on the party - work is absolutely killing me right now. I haven't been able to work on my engine for many weeks, and yesterday was a good example of why: 6 am on the job, serious problems arise at one of the plants, two PLC programmers and myself hang in there until 9:30 PM - and I'm still 45 miles from home. Get a call for online assistance at 1:00 am, then again at 5:30 am. I need a nap... or an epic cup-o-Jo.
 
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Old Oct 12, 2016 | 09:14 AM
  #73  
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Originally Posted by Tugly
Looking at the graph, one would need to know the normal values to decipher it. ICP would be 500 PSI at idle, your scale shows 7000 PSI or 85 PSI. I'm not trying to criticize or anything like that, my friend - I just feel the need to have good information if a reader is going to follow along and learn this stuff. The highest scale we will ever need on anything for the truck is 3500. The RPMs never top that, the ICP never tops that, the Fuel Injector Pulse Width should never top that in microseconds while running, the TC slip can't top that, and I'm almost certain I'm over looking a PID - but 3500 is the absolute scale limit we will never need to cross. When I want to see a fluctuation amplified, I squeeze the range. To explain - say my idle has a wild fluctuation at 700 RPM, I could set the scale minimum at 600 and the max at 800. That amplifies the fluctuation about 17-18 times.
Perhaps it is because we are used to looking at different types of data, but I don't see any concern looking at a value graphed as "80" knowing that it is really 8% (80% or .8% don't make any sense at idle).

Manipulating the graph position of the PIDs to overlay them should give a fair amount of info about the inverse relationship and fluctuations between IPR% and RPM.

Whether any conclusions can be drawn from that behavior or not, I don't know It looks to me that either IPR is stumbling (IPR sensor) and the RPMs are bouncing in response to that, or more likely that the RPMs are stumbling due to fueling issues (air?) and the IPR is reacting to that stumble. Chicken and the egg.

But we know the Hutch hasn't been done, so that increases the likelihood of the second, plus the fact that the Hutch is a good thing to do regardless and can either solve or rule out that possibility.

I guess it is fair to say this type of graphing shouldn't be considered "written analysis report quality" as I don't include any type of written explanations as I would in the professional world.

In my professional world I would graph the actual values, error values, flag the reliability based upon the anomalous values found in the log file, then use inset graphs without values to show that same relationship the overlay shows.

The individual data values are all available in the log file, if one needs to see a particular absolute value.

I would also point out that the graphs I post are only a snapshot of a particular set of data I find to be of interest or possible value. Others would surely find other sections of interest. Don't be shy, graph and share whatever you like, I'm ready to learn

I know Rich is a "numbers guy" and these kinds of things can irritate numbers guys, but I do think it is fair to say the info is easily understood by those who know the ranges of the values and such. I'm okay if you're irritated, Rich, especially with your current workload.

If I'm doing it wrong and the graphs are not of value, correct me. Just remember, I'm a little slow- you may have to repeat it a few times
 
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Old Oct 12, 2016 | 09:15 AM
  #74  
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Throwing my two cents in here: There are certain tasks on these trucks that need doing over time from preventive mtce perspective. In my opinion the following have a limited useful life:
IPR
ICP
EBP

Given the high mileage of this engine, why not replace at least the first two and check the condition of the EBP. I am not at all saying that the problem will be fixed. The IPR, ICP and EBP all work in difficult environments. Their performance is directly linked to proper running of these diesels and many have commented over the years-wow, the engine is... since doing the replacement.

That said, this problem has the symptoms of a marginal CPS/connection or air in the fuel. If the RPM info to the PCM is just suspect enough that the PCM is correcting for that bad info, the PCM may not see a problem with the circuit. And certainly air in the fuel damages injectors enough to warrant fixing the worst causes, even if not going the whole route with a Racor filter. Racor has a good writeup on their site about this common problem.

If I am wrong, keep the old sensor in the glove compartment.

Over the years, I have used the "list of most probable causes" method of troubleshooting. When a part is either suspect or old, why not replace. We have all read enough stories or experienced strange conditions ourselves to know that electronic parts by definition are flaky.
 
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Old Oct 13, 2016 | 06:08 AM
  #75  
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Originally Posted by ExPACamper
...I know Rich is a "numbers guy" and these kinds of things can irritate numbers guys, but I do think it is fair to say the info is easily understood by those who know the ranges of the values and such. I'm okay if you're irritated, Rich, especially with your current workload.

If I'm doing it wrong and the graphs are not of value, correct me. Just remember, I'm a little slow- you may have to repeat it a few times
Dude... If I'm coming across as cross, then I must have lost my touch at the keyboard. I'm sorry if it came through that way - maybe I should keep the fingers at bay before no less than 2 cups of coffee have had a chance to impact my zombie mode.

I see that IPR/RPM in perfect sync with each other, and it makes me go "Hmmm. The IPR is compensating for something." IPR is a command, it is reactionary on a stock tune - so I don't suspect it leads the problem, but follows.
 
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