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Lsj Crank but No Start

7K views 4 replies 2 participants last post by  skyluck93 
#1 ·
hello guys, i was driving back home on a bumpy road (i wasnt going faster then 20mph), when suddently, my car started to missfire. so i stoped on the side of the road, on the idle the car would run fine. so i turn it off and start it again, everything looks fine until i put it in gear and try to accelerate, it immediatly missfire when accelerating and die 4 feet away.... since then, car would only crank, without firing, i got a check engine light with no code P0000, even disconnecting the battery for a day, it would reappear instantly when turning the key to the 'on' position, got no passlock light. its a 2005 cobalt ss sc 2.0 lsj stg2 gm.

here a list of what i've done
-replacing the crank sensor with a brand new one
-i've check all my fuse like a hundred time, everything is ok even the one on the BCM
-swapped some relay (may try to reswap some more just 2 be sure i didnt swap 2 relay that could has been bad)
-i've ground the ecm to the body
-battery is 4 months old, been put on the charger to make sure i got enought power
-having another car boosting the cobalt
-got fuel going to the injector, smell fuel when i tried to start it and i also hear the pump buzzing
-got 13volt the the first pin (the one to the left) while battery is charging at 14.5volts, but no voltage on the other pins, even when cranking (so no fire to the spark plug, i've check for spark with a spark tester, some of my friend even took the whole coil with a plug on it to see if he would be electrocuted but he didnt feel anything)
-i have also unclip the PCM connector and replug them to make sure connector are well in place
-maf sensor and first 02 sensor is brand new from the last owner, fuel filter has been change too
-i've put 4 brand new acdelco spark plug 400miles ago
-i test 4 random connector for voltage, 2 of them had 5.02v and the 2 others had 13v, so i think the ecm should be good ?
-tried the passlock relearn where you tried to start the car, let it at the on position for 10minute then to off for 5 sec and repeat it 4 times, did it twice, even if the passlock light is off
-cleaned the throttle body (it was really dirty)
-i bought the car in december 2016 and store it for the winter, start it every time i went to shovel around my garage, started everytime with no issue
-drove 450miles after storage,i was having poor fuel consumption too, even when granny driving i was having 19mpg or 12,4L/100km

So after all, i got fuel sending, engine is cranking, but i got no spark at all, got a check engine light, tried with 2 different scanner, couldnt see the code. i know this kind of trouble are really common, i think i have check every post on the internet over and over and over and i never saw an answer
sorry for my bad english, but people in my community wont help me, they just want i part out my car ....
if anybody got wiring diagram of ecm or something that can help me is welcome =)
 
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#3 ·
got 110k miles on it, i painted the valve this winter during the storage and timing chain looked tight, havent done a compression test, wouldnt think it would be a timing chain related problem, cause at first when it missfire, i've put it in neutral and everything was fine, i turn off the engine then restart it, everything was fine until y start to move, it stall by itself and since it would not make any sparks
 
#4 ·
If you can start the car, then with it running, disconnect the electrical clip from each coil one at a time. If the coil is good, the car should sputter at idle until you plug it back in. If nothing happens, then you have bad coil or coils, which I suspect since you aren't getting spark. I had two coils go bad and it idled bad. If one coil is bad, it may idle fine, but stumble and stalls when under load (or put into gear)
 
#5 ·
ill make a resume, engine will crank, but won't start because the 4 spark plug are not firing, i want to know what can cause a 2.0L lsj to not making any spark, every fuse is okay, change every relay inside the fuse box and at the bcm, today i have changed the fuse box and it still not starting
 
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