Starting and Rough Idle then Shutdown issue

Steve T

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Here is my issue: 2011 LR4 5.0V8 139K
GAP tool shows no codes?

Wife driving Truck - pulls out from stop sign accelerates to 20-30mph (all normal). Truck goes black and shuts off. she glides to a stop (still in gear) car dead on side of road. At this point i'm not sure if she tried to start the car while in gear or not but symptoms are same when I show up and try to put car back in park.

Car is off - manually shift the car into park and try to start., dash light show starts (multiple flashing) - loud grinding noise from shifter and car trys to turn over. car starts momentarily but only when I step on accelerator pedal (as if not getting fuel) extremely rough idle as if the car is going to shake apart. shift the car back into N and then back to P and it dies.

Attempt again, car in P. dash light show starts again (multiple flashing), car trys to start, same symptoms, now car ignition process continues and will not stop until start button depressed again. try a few times and same symptoms. car starts for a few seconds only after accelerator pressed - extremely rough and then the car dies when you move shifter or it will die on its own after a few more seconds.

Battery tests fine. 875 amps when starting volts were 14.4V now showing 12V - mostlikkely after a few start attempts of draining the battery. Car is still dead.

Any thought?
 

jlglr4

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I think you need to try to get the codes off the car before you can begin to figure this out. Everything going black sounds like an electrical problem, but the grinding noise from the shifter and the fact that it will sort of start roughly with the accelerator pressed sounds like something mechanical. Also, not sure what you mean by “dash light show starts (multiple flashing).”

Some cars used to have a “clear flood mode” when you floor the accelerator and try to start, which would actually limit the amount of fuel getting to the engine to help clear a flooded cylinder. Not sure if the LR4 does this or not, but could indicate an injector that has gone bad wide open, causing a cylinder to flood (I had this happen to my volvo once).

But this could be lots of things. Really need those codes for a starting point.
 

f1racer328

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Some cars used to have a “clear flood mode” when you floor the accelerator and try to start, which would actually limit the amount of fuel getting to the engine to help clear a flooded cylinder. Not sure if the LR4 does this or not, but could indicate an injector that has gone bad wide open, causing a cylinder to flood (I had this happen to my volvo once).
We do have this feature. Floor the pedal (can’t remember if you have to depress the button or not) and it’ll cut fuel.

Can crank with no start if you desire.

Battery terminals tight?

Does anything look wrong under the hood? Accessory belt, maybe take a peak at the timing chain through the oil cap. I agree though, you should check for codes.
 

hickersb

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Here is my issue: 2011 LR4 5.0V8 139K
GAP tool shows no codes?

Wife driving Truck - pulls out from stop sign accelerates to 20-30mph (all normal). Truck goes black and shuts off. she glides to a stop (still in gear) car dead on side of road. At this point i'm not sure if she tried to start the car while in gear or not but symptoms are same when I show up and try to put car back in park.

"goes black" -- Do you mean lost ALL electrical, or just engine died?

We do have this feature. Floor the pedal (can’t remember if you have to depress the button or not) and it’ll cut fuel.

Can crank with no start if you desire.

This probably explains why I had such a tough time starting the LR4 when still wearing snowshoes.
 

Steve T

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Battery terminals tight?

Does anything look wrong under the hood? Accessory belt, maybe take a peak at the timing chain through the oil cap. I agree though, you should check for codes.
battery terminals are tight
GAP codes:
C1A46-64 (68) Actuator plausibility check, mismatch between motor drive current and resultant force
&
U0159-00 (2E)
lost com to parking brake unit

last time I tried to start, I got "performance restricted" message on instrument cluster (never seen that before) and now may parking brake light is flashing as if its trying to engage with a loud screeching noise.. I had this loud screeching noise last time may P-Brake failed to unlock and had same flashing brake light on dash.

car continues to try to start (turn over) constantly and will not stop start sequence until I manually press the start button again to interrupt the start.
 

hickersb

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engine died and instrument cluster went black

OK, weird. I was going to suggest checking ground points (esp the one under the pass wheel well) but if it is cranking fine now, I assume ground path is established.

battery terminals are tight
GAP codes:
C1A46-64 (68) Actuator plausibility check, mismatch between motor drive current and resultant force
&
U0159-00 (2E)
lost com to parking brake unit

last time I tried to start, I got "performance restricted" message on instrument cluster (never seen that before) and now may parking brake light is flashing as if its trying to engage with a loud screeching noise.. I had this loud screeching noise last time may P-Brake failed to unlock and had same flashing brake light on dash.

car continues to try to start (turn over) constantly and will not stop start sequence until I manually press the start button again to interrupt the start.

It's weird you don't have any codes for the ECU. I don't know what your issue is, but I can tell you when I had an injector stuck open, I did get codes for misfire.
 

jlglr4

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Did you happen to have a roof drain leak in the recent past? Seems like these strange situations are most often attributed to corrosion at the central junction box due to that particular scenario.

Otherwise, things that come to mind are rodent damage to the wires behind the battery box, and some connection between the instrument cluster and the central junction box - I can only remember a post about it, but can’t recall details.
 

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