Crank to Run, engine stops turning over. As if DIS synced on wrong cyl

CottonPicker

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2005 Buick Lesabre
This occurs cold start only. Miles 121,242. First time @ 116,059, then 116,559, 116839, 117497, 119,087, 119.020, 120,900, miles. No crank learn - No scan tool. No CEL/SES
Delphi Cam and crank sensors @ 94,xxx. Wiring Clean and terminal ends tight using oem male with drag test. Engine clean.
New AC Delco DIS module, with file flat base Grds cleaned and thermal paste @ 110,xxx miles. Injector sent out @ 110,000 for clean and flow - no leaks. Reman Delco starter @ aprox 85,xxx
If coolant or fuel was entering any cyl I believe there should be smoke or a smell out of tail pipe. THERE IS NONE. No raw fuel, or sweet coolant. I move to the rear of the car very fast to see/smell.
When starter stops, I immediately release the key to run, two seconds I reengage the starter and it starts normal, No misfire, engine sputter, no movement in engine bay after. Fuel reg vac hose NOT wet.
No scan tool. Went to local shop asking but this occurs so intermittent it would cost $$ to watch.
I am about to buy a Chinese Tech-2 Plus already ordered A/C Delco / GM Crank and cam sensor, cam magnet, t-chain set, WP ect to replace.
PCM OEM. Have Delco replacement ready.
(By the way. For 3.8L T-chain set Cloyes made in Taiwan. Melling USA)
Your thoughts and suggestions.

PS. When the engine cranks I hear each time the cylinders reach a compression stroke and count them. Normally, not occurring, the comp strokes hat 3 to 5 time before run cycle. When failure occurs or CRANK TO RUN ERROR, the compression strokes hit 2 or 3, then the starter stops and the engine won't turn over. I do not hold the key and allow the starter to remain engaged. Each time I release the key and restart as described.
 
I find it interesting that when the problem occurs, 2 seconds later, the engine starts as if nothing happened. I think that I would consider taking the time to prove that excessive mechanical load is causing the starter motor to stall. Fortunately, stall current on a series wound DC starter motor should go very high and very quickly. If the problem consistently occurred then you could use a digital clamp-on AC/DC current meter with Min/Max storage capability. However, the intermittent nature probably makes this an ineffective test method.

If you have not made progress at the time of reading this response, one idea to consider is to install a high current switch on the starter motor main electrical feed cable with an audible alarm. Something like what I have described in the attached document. I'm assuming that a 300 amp rating will be high enough to make this idea effective and hopefully will serve as a practical test that will help. I own several LeSabre's of this same vintage, so I'm especially interested in what you find. If indeed you are stalling starter motor due to excessive load, keep in mind that excessive load could be caused by several possible reasons to include some type of strange binding in the starter bendix gear to flywheel contact. But at least by proving that the the starter motor is stalling due to high current, you're pursuit can then be focused on finding the reason for the increased load (excessive stater motor current). I personally have never experienced anything that would cause the 3.8L start up timing to suddenly go so advanced that it stalls the starter motor. Perhaps another member has some ideas to offer. This problem is so strange.
 

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What is a DIS module? Are you referring to the thing that the coils sit on? If so then that is the Ignition Control Module aka ICM.
 
Sorry for using old terminology names. Pre OBD-2 the name was DIS module or Direct Ignition System Module. In 96 the feds took over mandating ICM or Ignition Control Module. Yes Sir the coils bolt on top of the ICM and then to the alum bracket.
(In the older days the DIS referred to the system actually. And the module was a DIS Module. Age has been creeping up.)
I'm open to your thoughts. Thanks
 
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RD_Atlanta Thanks for your input. I've giving this some thought. I have a clamp on Start/Alt tester but haven't used it in this failure mode.
My thoughts on monitoring the B+ draw would conclude high amps. Something is stopping the engine from cranking speed to the run cycle. Or 125/150 RPM to 550 RPM run speed. In my case I think the amps would read very high.
I am not closed off to this or any part anyone has.
I have the Timing chain set and will begin the repair along with new Cam & Crank sensors. I bought a Cloyes and Melling set. Cloyes is made in Tiawan, Melling the box states MADE IN USA. The crank gear is packaged in plastic inside, sticker is made in Taiwan. Chain in a box no made in. No OEM ava. New A/C Delco Crank sensor made in Mexico. Don't have cam gr. Cam Adjuster Magnet (WVE) - made in Mexico. New A/C Delco WP made in China.
 
Not sure I fully understand what the problem is, but have you considered a failing starter?
 
You know, it sure could be a failing starter. I would think you would see it on the amp meter (either via high amps on stall current or via a sudden drop in current (if there is a problem with the commutator or one or more of the brushes).

It just occurred to me that this is very similar to the problem that Cotton Picker is having with his. It will be interesting to see what is causing their strange starter issues.

 
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