No Spark 3800 apv helpppppppppppp!

[mrtooter]

Van just quit on highway - is this any indiction on were to look?

new crank sensor put in,about 4 used ignition modules, back probed all the wires in ignition circuit to the computer for continuity, all is well, checked all the fuses including 20amp in engine compartment, fuel pressure if good, injecters are comeing on when cranking, checked all grounds and cleaned them, did a diagnostic test from shopkey5 still no spark,

any ideals on were else to look my wife is driving me nuts this is her van to get all the grandkids and drive me nuts even more. a lose , lose situition lol

think hard what havnt i checked? thanks in advance

[richtazz]

check the harmonic balancer to see if it separated and re-check the crank sensor for a signal. Just because you recently replaced it doesn't mean it isn't bad.

[mrtooter]

balancer looks ok , any ideal how to check the cranks sensor while its hooked up?

[richtazz]

unplug the connector, hook up your ohm meter to the crank sensor, and have someone crank the engine. The ohm meter will detect a change in resistance in the sensor as the shutter on the balancer passes through it if it's working. Also double check the wiring harnesses at the ICM. They are fairly common to get corroded, or it's easy to bend them while intalling a new module.

[mrtooter]

were exactly should i put the ohm meter and should it be set on ohms or volts/ thanks for your help ,

[richtazz]

set it to ohms. There are 4 spades in the sensor itself, and each adjacent pair controls 3 cylinders. The crank sensor is a dual hall effect switch which sends a signal to the ECM each time one of the reluctor blades on the harmonic balancer passes through it. You must insure that the harmonic balancer doesn't touch the crank sensor. If your van is 93 or older, the crank sensor is adjustable, and the air gap needs to be set when installing the sensor. If it's misaligned, it can allow the balancer to hit the sensor, causing it to fail and the van to stall. To test, put the red probe of your multimeter on the outside terminal, and the black on the terminal next to it, and crank the engine. the reading should change as the harmonic balancer reluctor passes through the sensor. Test the other half in the same manner. If you get no difference in reading, then the sensor is bad.

[mrtooter]

my van is a 93 with a new gm rebuild 3800 engine , the crank sensor does not appear to be adjustable as it sits on a pin in the middle and has a bolt on each side. im willing to buy a new icm but i have tried 3 or 4 used ones from the junk yard with no luck, we have spent 3 full days doing tests on it, its not worth spending alot of money on so any help u can give im very thankful for.

[SAGE12]

Originally Posted by mrtooter

my van is a 93 with a new gm rebuild 3800 engine , the crank sensor does not appear to be adjustable as it sits on a pin in the middle and has a bolt on each side. im willing to buy a new icm but i have tried 3 or 4 used ones from the junk yard with no luck, we have spent 3 full days doing tests on it, its not worth spending alot of money on so any help u can give im very thankful for.

IT NOT THE ICM
I'M HAVEN SAME PROB ON MY CENTURY
I HAVE NEW CRANK SENSOR NEW ICM & NEW CEM NO CHANGE

[SAGE12]

Originally Posted by mrtooter

my van is a 93 with a new gm rebuild 3800 engine , the crank sensor does not appear to be adjustable as it sits on a pin in the middle and has a bolt on each side. im willing to buy a new icm but i have tried 3 or 4 used ones from the junk yard with no luck, we have spent 3 full days doing tests on it, its not worth spending alot of money on so any help u can give im very thankful for.

IT NOT THE ICM
I'M HAVEN SAME PROB ON MY CENTURY
I HAVE NEW CRANK SENSOR NEW ICM & NEW CEM NO CHANGE

[jeffcoslacker]

"The power of Christ compells you..."

[mrtooter]

every car is different ,i over look nothing im beyond the basics, time to get down and dirty, i need some high tech help!

[jeffcoslacker]

Run an alternate 12v supply to the ICM and see what happens....

[mrtooter]

i dont recall 12v going to the icm only 5.5volts from the computer,, i ran a bunch of tests provided by shopkey5 who gets them from general motors

i have entire wiring diagram and all general testing methods,

[jeffcoslacker]

Originally Posted by mrtooter

i dont recall 12v going to the icm only 5.5volts from the computer,, i ran a bunch of tests provided by shopkey5 who gets them from general motors

i have entire wiring diagram and all general testing methods,

Yeah, I think you're right.

Check continuity of the coilpacks yet?

[mrtooter]

i have replaced entire assebbly icm and coil packs as a unit, mind you they were all used from the scrap yard, and one that was known working