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Oldsmobile/Buick Repair/Lesabre won't start part 2

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QUESTION: Hi Tom, I thought I'd summarize the problem and symptoms, both good and bad, in the hope that rewording the problem and symptoms might reveal a conclusion of sorts.

GOOD: 1) fuel pressure at the rail; 2) spark; 3) starter crank; 4) 5-volt system; 5) ICM base ground after sanding it; 6) ICM circuits P (power), K (ground), N (12v to cam & crank sensors); 7) Passkey 3 (probably works okay); 8) fuses.

BAD: 1) no start after cranking; 2) no noid light signal; 3) no check engine light; 4) no code reader readout; 5) trouble code icons keep flashing- pin 16 (battery pos.) shows 12 volts; pin 2 (bus pos. line) never stabilizes, but fluctuates from .2 to .7 volts; pin 4 (chassis grnd) shows 6mv; pin 5  (signal grnd) shows 16mv.

UNKNOWN:  1) condition of all relays; 2) whether every injector works properly; 3) signal from PCM (still looking for wiring diagram); if Check Engine bulb is dead; 4) scan with data correct.

QUESTIONS:  1) I didn't try the LED test light, but If I get good spark, does this mean that I also have a good crank signal?  2) Does the signal from the PCM go to the ICM?

ANSWER: GOOD DAY JOHN,LAST QUESTION FIRST,YOU HAVE HAVE GOOD SPARK, YES, THE CRANK SENSOR IS GOOD.
YOUR BAD QUESTION #1 THIS SOUNDS LIKE A BAD PCM OR WIRING FROM THE PCM TO THE INJECTOR HARNESS. IT ALSO SOUNDS LIKE A BAD PASS LOCK SYSTEM,BUT THE CK ENG LIGHT WOULD LITE AND YOU WOULD GET A DATA READ OUT WITH YOUR SCAN TOOL..AND YOU ARE NOT !!!!SO WE GO BACK TO THE PCM. PCM SUPPLIES POWER  OR SIGNAL I SHOULD SAY TO THE IGN MODULE AFTER IT RECEIVES THE SIGNAL FROM THE CRANK SENSOR.. IF I AM READING THIS CORRECT IF YOU WERE TO SPRAY STARTING FLUID INTO THE THROTTLE BODY YOUR ENG WOULD START [CORRECT.]THE ENG HAS EVERYTHING IT NEEDS BUT INJECTORS THAT OPEN...[PULSE] WOULD YOU TRY THIS AND LET ME KNOW IF IT RUNS LIKE THIS...THIS IS STRANGE..CAN YOU ALSO CK THE WIRING HARNESS GOING TO YOUR PCM AND JUST MAKE SURE ALL THE WIRING LOOKS TO BE IN GOOD SHAPE. ALSO TUG ON THE WIRING HARNESS AND SEE IF THIS WILL START WHILE SOMEONE IS CRANKING THE ENG FOR YOU. I WANT TO KNOW IF THIS ENG WILL START UP ON STARTING FLUID,, HAVE SOMEONE CRANK THIS OVER WHILE YOU SPRAY IT INTO THE THROTTLE BODY. JUST AS A TEST. !!!!! ALSO WHAT DO YOU MEAN BY>>>> TROUBLE CODE ICONS KEEP FLASHING..IN YOUR SCAN TOOL OR ON THE DASH????

SO TO SUM THIS UP IN MY MIND,:::
NO CK ENG LIGHT
SCAN TOOL WILL NOT READ ANY CODES OR DATA.
NO INJ PULSE
SOME OF YOUR VOLTAGES ARE GOOD. I WILL BE HERE LET ME KNOW WHAT IS UP....GOOD LUCK TO YOU,,TOM


---------- FOLLOW-UP ----------

QUESTION: Hi Tom, the trouble code icons are on the scanner.  The ones that match my vehicle show at the top of the scanner's screen.  The systems that are successfully read show as stable icons, which in my case are three icons.  The other five system icons just keep flashing on the screen, and never stabilize.  This possibly corresponds to the data link connectors I mentioned in "BAD" above.  With the key "On," some readings look odd to me.  However, I am not a mechanic, and it is possible that the odd readings actually mean the the PCM is doing its job and is properly reporting odd conditions within the various systems.

I have an "oops" to report.  My "Service Engine Light" does come on.  I was looking for a "Check Engine" light, which my panel does not have (insert embarrassed grin here).  Also, the engine runs with starter fluid.  Even though I tried to rule out crank sensor, one ex-mechanic at AutoZone had a similar vehicle, and is 80% certain that, even with good spark, the crank sensor is the problem.  And what do you think about a cam sensor, which my 2003 LeSabre has?

I'm trying to rule a few things out before removing the passenger seat and rolling up the carpet to get at the PCM.

ANSWER: HI JOHN, I WILL SKIP AROUND HERE A BIT, IF YOUR CRANK SENSOR WAS BAD YOU WOULD NOT HAVE SPARK..[NO WAY] SO YOU CRANK SENSOR IS GOOD. 95% OF THE TIME IF THE CAMSHAFT SENSOR GOES BAD THIS USUALLY WILL SET A CODE,BUT MOST OF THE TIME THE ENG WILL START BUT HAVE A LONG CRANK TIME.
IF THE CAM SENSOR THROWS A CODE THIS SOMETIMES IS NOT THE PROBLEM,SOMETIMES IT IS THE TIMING CHAIN THAT IS JUMPED TIMING OR JUST TO SLOPPY AND THE CAM SENSOR PICKS UP ON THIS LOOSE CHAIN AND SETS THE CODE. THIS IS NOT YOUR PROBLEM..AS FAR AS YOUR ICONS GO ON YOUR SCAN TOOL I DO NOT KNOW..I AM USED TO READING A GM TECH 2 TOOL. SO I CAN NOT HELP YOU WITH THE ICONS. THE GOOD NEWS IS YOUR ENG STARTS ON STARTING FLUID..SO THIS BRINGS US BACK TO NO PULSE TO THE INJ'S...YOU HAVE SPARK, FUEL PRESSURE  AND THE INTERNALS OF YOUR ENG ARE GOOD...YIP EEEEE.
OK LETS GO BACK TO THE PASS LOCK SYSTEM..I WANT YOU TO TURN THE ING KEY ON AND LEAVE IT ON FOR 30 MINUTES. MAKE SURE YOUR BATTERY IS GOOD AND STRONG,TURN ALL THE LIGHTS OFF AND RADIO AND SO ON.. DO NOT CRANK THE ENG OVER IN THAT TIME FRAME. AFTER 30 MIN'S,TURN THE KEY OFF AND THEN TRY TO START THE CAR...THIS MAY RELEARN YOUR PASS LOCK SYSTEM..WE HAVE HAD TIMES THAT THE PASS LOCK SYSTEM WILL NOT BLINK OR LIGHT UP OR SET A CODE ON. THIS SYSTEM IN YOUR CAR CAN NOT BE TESTED WITH A OHM METER. IT NEEDS A [[YOU GUESSED IT]] A GM SCAN TOOL OR SIMILAR GM SOFT WARE. THIS SYSTEM SHOULD SHUT DOWN THE STARTER AND [INJ PULSE]..BUT,,,,SOMETIMES THE PASS LOCK SYSTEM SCREWS UP TAKING SOME OF IT OUT NOT ALL... ..LET ME NOW WHAT HAPPENS WITH THIS...GOOD LUCK TO YOU,,,TOM..

---------- FOLLOW-UP ----------

QUESTION: Hi Tom, I did the Passkey relearn and the car won't start.  I should have mentioned this before, but I tried the relearn several times before with the same results.

Answer
HI JOHN,,OH NO..OK SO IF WE HAD A SCAN TOOL THAT COULD TALK TO BCM AND PCM WE WOULD KNOW IF ONE THING OR THE OTHER IS NOT RECEIVING THE SIGNAL TO DO SO. IF YOU WANT TO KEEP GOING ON THEN YOUR NEXT MOVE IS TO GET A HOLD OF THE INJ HARNESS AT THE ENGINE AND START OHMING OUT THE HARNESS FROM THE INJ HARNESS TO THE COMPUTER AND SEE IF THERE IS A OPEN IN THAT CIRCUIT TO THE PCM..AND THEN YOU WILL NEED TO FOLLOW THAT OVER TO THE PASS LOCK SYSTEM. IF YOU DO NOT FIND ANYTHING.HAVE YOU LOOKED AT ANY OF THE WIRING HARNESSES YET JUST TO SEE IF YOU SEE SOMETHING UNUSUAL ??? THIS IS ONE OF THESE CARS THAT I WOULD REALLY LIKE TO HAVE HANDS ON TO FOLLOW THINGS OUT...MY MONEY IS ON THE PASS LOCK SYSTEM NOT COMMUNICATING WITH THE PCM...I WOULD REALLY LIKE TO HELP YOU WITH THIS BUT THERE IS ONLY SO MUCH I CAN DO BY MEANS OF EMAIL..BUT IF YOU NEED MORE INFO I WILL DO MY BEST FOR YOU. WHEN YOU DO FIND OUT THIS PROBLEM [PLEASE GET BACK TO ME]....GOOD LUCK TO YOU TOM.....

Oldsmobile/Buick Repair

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TOM SHEETS

Expertise

Can answer all questions pertaining to mechanics of GM cars from 1965 to present. I will answer questions from 6:00 am to 10 pm est.. I will not take diesel or paint questions. If this olds and buick section is maxed out you can get to me in the chevrolet section...

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I have 30 plus years experience in servicing these cars. I can answer questions on carburetor, fuel injection,ignition systems, suspension, brakes and abs, cooling systems,a/c and heater,manual transmissions, rear differential and electrical system,charing system and battery. I am a Master ASE certified mechanic in all 8 categories: - Brakes - Heating and Air Conditioning - Automatic transmission - Clutches and Transaxle - Engine performance - Engine repair - Electrical - Steering and suspension I am certified for NYS inspection and clean air insp.

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I am a Master ASE certified mechanic in all 8 categories (see above) I am an Air Conditioning/Freon recycling specialist with ASE. I have at least 4 years of technical training and many hours of continuing education.

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many customers in our busy shop for the past 30 plus years

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