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Power loss, Defueling or Limp Mode Issue??

domunique

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In need of some help on this issue!! I'm moving across to the west side of WI and I need to get my crap home this weekend.

2000 GMC K3500 6.5 Diesel has lost all power over ~2200 rpm. Started doing this the other day.
taking off from a stop you can feel the power start dropping off a little before it shifts to 2nd and sometimes a fishbite or 2
2nd gear if you put it down WOT it will get stuck there and wind up to ~3000 RPM and not shift till you backoff the pedal
if you set the cruise and hit even a small hill it will downshift to 3rd, RPM's jump and speed keeps dropping.
Only way to maintain Hwy speed is in OD being careful not to let it downshift. Keeping it under ~2200 RPM.

Here is what I have checked and have made no imporovement, WHAT AM I MISSING????

No SES light or any current codes. Can sometimes get one for over-boost with the TMaster, have since dialed it back to max at 8-10 PSI boost pulling my trailer never had a powerloss like this before even when it coded for over-boost.
Pulled the Lift pump and blew air back to tank to possibly clear the sock. Ran outlet side to a clear line into a bucket. Appears to be good flow, nice solid stream through the 3/8 line and no air bubbles seen.
Clear line on the IP inlet - No Air bubbles seen while driving.
Fuel Pressure at water drain: key on builds to 5-6 PSI. Driving it maintains ~5.5 PSI all the time including during the defuel event
Not seeing any pressure on the return line outlet. Blew air back to tank
Put in a new WIX fuel filter


Had a helper last night so I had him drive so I could watch the laptop better.

TDCO -1.5 something
Timing Actual & desired follow each other closely
IAT's under 180
Max Boost ~23 minus 15 at startup = 8 PSI about what the guage on the pillar pod reads
Fuel solenoid closure time in spec between 1.5ms – 1.9ms per http://oregonfuelinjection.com/pdf/gm-6.5-EFI-diagnostic.pdf

Watching the fuel rate mm3 I can see that WOT will put it up in the 70's and as RPM's get higher the rate keeps dropping. At WOT 2nd gear it will tack out ~3100 rpm and fuel rate will be down around 60 and not change even if you vary the pedal between 3/4 and the floor. Slowly releasing the pedal the rate does not change until you back off enough to shift to 3rd, RPM's drop and the rate will go back up and start to decrease againg as you approach 3000 RPM.

What is going on??
Can anyone tell me if the Fuel rate being displayed in the Auto Enginuity tool is a measure of actual fuel rate being deliverd or is a rate the computer is commanding the pump to deliver?
If it is a commanded rate then it appears to me that my problem is something giving the computer bad data and it is defueling because of it.
 
I'd check temps on the lap top it sounds like it's defueling from overboost or high IAT. could be a bad sensor causing it
 
Temps look ok it was about 45F when I logged this.
What I am not understanding is why when I have the pedal on the floor and as RPM's increase fuel rate keeps dropping


Time Coolant Temp IATemp Boost (PSI) Fuel Rate (mm3) RPM
10:42:27.441 126 55 14 15.18 676
10:42:28.408 126 55 14 14.871 684
10:42:29.385 126 55 14 30.361 1157
10:42:30.521 126 55 14 30.361 1314
10:42:31.465 126 55 14 30.361 1398
10:42:32.408 127 55 15 30.361 1450
10:42:33.353 127 57 15 33.459 1616
10:42:34.297 127 57 16 38.106 1843
10:42:35.233 127 61 17 41.514 2017
10:42:36.385 127 68 19 43.992 2303
10:42:37.321 127 77 21 35.937 2010

It just shifted to 2nd gear and I floored it here.

10:42:38.273 127 86 21 66.298 2352
10:42:39.209 127 97 24 75.592 2323
10:42:40.161 127 109 24 75.592 2310
10:42:41.097 127 115 24 75.282 2402
10:42:42.249 129 120 23 73.424 2457
10:42:43.177 129 122 23 67.537 2492
10:42:44.121 129 122 23 71.875 2609
10:42:45.073 131 126 23 70.635 2654
10:42:46.017 131 127 23 69.706 2726
10:42:46.961 131 129 23 65.059 2681
10:42:48.106 131 131 22 57.314 2759
10:42:49.049 133 131 23 67.227 2838
10:42:50.025 133 133 23 65.988 2869
10:42:50.961 133 133 23 65.678 2893
10:42:51.897 135 135 22 64.749 2929
10:42:52.849 136 136 22 64.439 2961
10:42:54.001 136 136 22 64.129 2992
10:42:54.937 136 136 22 63.51 2989
10:42:55.889 138 138 22 63.2 3018
10:42:56.825 138 138 22 63.2 3020
10:42:57.754 140 140 22 63.2 3050
10:42:58.713 140 140 22 63.2 3065
10:42:59.849 144 144 22 63.2 3068
10:43:00.793 144 144 22 63.2 3098
10:43:01.738 144 144 22 62.89 3090
10:43:02.681 144 145 22 62.89 3093
10:43:03.625 145 145 22 62.89 3119
10:43:04.561 145 145 22 62.89 3115
10:43:05.713 147 147 22 62.89 3104
10:43:06.649 147 147 22 62.89 3138
10:43:07.585 149 147 22 62.89 3114
10:43:08.537 149 149 22 62.89 3140
10:43:09.481 149 149 22 62.89 3151
10:43:10.422 151 149 22 61.341 3141
10:43:11.577 153 149 22 58.553 2375
10:43:12.513 154 149 24 70.945 2460
10:43:13.449 154 149 24 72.494 2464
10:43:14.403 154 149 24 72.184 2467
10:43:15.337 154 151 24 71.255 2494
10:43:16.273 156 151 24 70.016 2544
10:43:17.417 156 153 24 60.722 2478
 
That is in Fahrenheit
Highest IAT on this test run was 153 deg F
Attachment might be easier to read
 

Attachments

  • GMC-Sierra 3500 Pickup-2000-April 09 2014.pdf
    52.6 KB · Views: 4
coolant temps are really low and IATs seem low as well. IIRC the fuel rate is about right, puts out max fueling in mid rpm and tapers off as rpm increases, db2 pumps do the same
 
where is the fuel injection regulator?
I don't think I have any vac lines going to the IP
 
More specifically, the resistor inside the PMD connector cavity.
But the amount are very small between different resistor value.
 
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