Yesterday while running errands, I started Giddyup (fully warmed up from running errands) and was about to put her in gear and drive off when she suddenly died...just cutoff ... she would still crank hard but NOT restart.

As she has never done anything like it before, I was startled and while I did see the red SKIM led come on while turning the key, I didnt pay much attention to it as I was also looking at all the other lights, including the check engine light, which was now lit.
I also popped the hood and cowl, looking for any signs but found nothing obviously amiss.

However, while I was standing by the DS door calling my daughter for a potential long range rescue, I heard a soft clunk (more then a simple relay click) from near the fuse box, or perhaps ECM, and when I tried her again, she more or less started right up.

I finished running my errands and got home without any further incident but when I hooked up the OBD2 reader to check for DTCs, there were no codes set in memory.

I am guessing that something is starting to go amiss with the SKIM module cutting off fueling or other electronic signals needed to start and I am open to any and all suggestions on how to proceed with diagnostics and fixes to prevent this from happening again!!!

I am specifically wondering --

1) if dying after a few seconds and then not restarting might be related to a failing SKIM?

2) What exactly are the symptoms of a failing SKIM in a 2005 KJ CRD ?

3) Will a failing SKIM set a DTC?

4) What MIGHT have caused her to die and NOT set a DTC??

5) What might have been the soft "clunk" (definitely not a light relay click) that I heard near the fuse box or ECM (in other words around the drivers side fender inside the engine compartment) after which she immediately fired right up?

TIA !!!

_________________
Horses in the stable:

"Giddyup" is my 2005 Liberty CRD
"Maya" is my 2005 Dodge Ram 2500 CTD powered by the mighty Cummins ISB 5.9 with 6spd G56 manual trans
"Mr Ed" is my 1980 Toyota Pickup Flatbed, 20R engine, 4 speed manual, NO power steering, NO A/C

The click/clunk was from the intake throttle re-opening under spring pressure. It shuts at key-off to reduce engine shake, then opens after about 10 seconds.

To me it sounds like your crank position sensor is going bad from heat soak. Common problem. How many miles, and have you replaced it before?

_________________
05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
RL super sliders, Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

Interesting…recently finished an extensive 200k timing belt service that included turbo, glow plugs, MAP and AAT and thermostat/coolant temp sensors but NOT the crank position sensor.

Wish I had thought to change it when the turbo was off.

That said, the engine died about 10 seconds after starting , and then wouldn’t restart….but if you’re saying that the
Intake throttle closes each time 10 seconds after key off even if the engine doesn’t start then it is likely that s what I heard. But the car had been sitting resting between errands for about an hour when i started it and when it died after and then wouldn’t start again….how could that be “heat soak” if it had been sitting for so long?

Thanks for clarifying your explanation…
Also any links to a thread about failing CPS would be much appreciated too!!!

_________________
Horses in the stable:

"Giddyup" is my 2005 Liberty CRD
"Maya" is my 2005 Dodge Ram 2500 CTD powered by the mighty Cummins ISB 5.9 with 6spd G56 manual trans
"Mr Ed" is my 1980 Toyota Pickup Flatbed, 20R engine, 4 speed manual, NO power steering, NO A/C

Also wouldn’t a failing CPS set a DTC?

_________________
Horses in the stable:

"Giddyup" is my 2005 Liberty CRD
"Maya" is my 2005 Dodge Ram 2500 CTD powered by the mighty Cummins ISB 5.9 with 6spd G56 manual trans
"Mr Ed" is my 1980 Toyota Pickup Flatbed, 20R engine, 4 speed manual, NO power steering, NO A/C

First thing to do is to get it scanned and see what P Codes are set.
They may tell you where or what direction to concentrate on.
Have you tried a different GOOD programed key?

Study the FSM, lots of good information on the SKIM and how it functions.
https://www.colorado4wheel.com/manuals/Jeep/KJ/2005JeepKJServiceManual.pdf

See section 8Q - 14 in the 2005 FSM (link above)

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Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
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A bad crank position sensor rarely sets a DTC, but there's a test you can do on it. Remove it and measure the resistance between pins. Heat it with a hair dryer while monitoring the resistance and if it starts around 1000 ohms and steadily climbs a few hundred it's probably fine. If the resistance shoots up or goes open circuit, it's bad.

viewtopic.php?f=5&t=79958

viewtopic.php?f=5&t=79631

_________________
05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
RL super sliders, Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

Thank you, that is good information.

Unfortunately the crank position sensor is so hard to access on a CRD that I'll have to wait to test it until I am actually replacing it ... but I will do that and report back what I discover.

_________________
Horses in the stable:

"Giddyup" is my 2005 Liberty CRD
"Maya" is my 2005 Dodge Ram 2500 CTD powered by the mighty Cummins ISB 5.9 with 6spd G56 manual trans
"Mr Ed" is my 1980 Toyota Pickup Flatbed, 20R engine, 4 speed manual, NO power steering, NO A/C

Work at it from below. You can reach the two fasteners for the heat shield, then there's just the allen head retaining bolt and the connector.

_________________
05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
RL super sliders, Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.