1994 5.9L gas has spark and fuel but won't startI

#11

herche54 , 07-14-2015 11:43 AM
Replaced the ECT and the engine still wouldn't start; not a peep. So my mechanic replaced the coil and it finally started and ran! Yet the old coil show arcing and it appeared strong. Now I can understand a coil getting weak enough that the engine won't start but this problem occurred while I was leaving a stop sign. Is there a way to measure coil strength? I do thank everyone for their speedy suggestions. I originally search this excellent forum for people's previous experiences and it gave me a good head start. Again, thanks. Bill
#12

HeyYou , 07-14-2015 11:45 AM
There is a specific tool for checking spark, but, all it tells you is if the coil has enough oomph to jump a fat gap. Conditions in the combustion chamber can be a bit different than just laying on top of the motor though. (so, the gap is actually pretty big.) I just use a sparkplug...... Spark color tells the tale

CAN YOU PLEASE CLARIFY THE SPARK PLUG USEAGE FOR TESTING COIL? HIGLIGHTED IN RED(SEE ABOVE)

HAVE A 1996 2500 8 5.9L
STAULED WHILE IDLING AND WONT START(CRANKS BUT NEVER STARTS)
EXHAUSTED ALL OTHER POSSIBLE CAUSES
. NOW I AM BACK TO THE COIL AND HAVING DIFFICULTY ON A METHOD TO TEST FOR SPARK. HAD TESTING ED PREVIOUSLY WITH A PIECE OF METALFOR GROUND AFTER DISCNNECTING ON OUT PUT POWER AND RECIEVED SPARK BUT NOT STRONG.......I DO OWN A MULTI METER IF THIIS HELPS WITH BAD COIL ......ORIGINALLY THOUGHT IT WAS OK DUE TO SPARK BUT FURTHER RESEARCH INIDICATED THAT THE SPARK SHOULD HAVE BEEN MUCH STRONGER. ALREADY REPLACED CRANK SENSOR....UGGGHHHH

THE MULTI METER IS A BIT OF A CHALLENGE ON SETTINGS FOR TESTING THE OHMS PLUS ......AS I .UNDERSTAND.........THIS MAY NOT PROVIDE ACCURATE RESLUT ACCORDING TO THE OLD POST,,BY HEYYOU,,,,,THE GAP THAT WAS MENTIONED IN POST AND DIFFERENT CONDITIONS IN THE COMBUSTION CHAMBER.

ANY AND ALL FURTHER SUGGESTIONS ON THIS TESTING PROCESS OR ANY OTHER INPUT ON CAUSE OF A RUNNING TRUCK THAT STOPS DURING IDLE AND WILLNO START ENGINE BUT WILL CRANK