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No Spark, Help, I'm Stumped

JHenline
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JHenline New Member

JHenline

Posted
Posted

I'm desperate guys. I've been searching and trying and implementing and testing for 3 days and I cannot figure out why I have no spark.  Working on a 2006 chevy 2500hd, 2wd with an LQ4 and 4l80e. I have crank, fuel, compression but no spark. What I've done so far
- verified <1 ohm resistance from each coil connector ground to battery negative terminal (brown wire) with key on and off

- verified battery voltage at each coil connector (pink wire) with key on
- verified pcm is sending signal for spark using data log in hp tuners when cranking

- checked and cleaned all grounds, all 4 wire harness to engine grounds, engine to battery ground, engine to firewall ground, battery to chassis ground, literally every ground I can think of and locate has been cleaned and reattached

- replaced all 8 ignition coils with known good coils from running engine

- replaced all 8 plug wires with known good wires from running engine

- replaced all 8 spark plugs with brand new ACDELCO iridium plugs

- deleted VATS

- verified good crank position signal by logging rpm while cranking in hp tuners

- checked and double checked all fluids, all full

Anybody experienced this and figured it out? Anything I have missed? I've been chasing this for 2 days now and can't figure it out. Any way to check pcm signal at coil connectors without a waveform scanner or fancy scantool?

Thanks for any input, suggestions, or help!

 

Formulabruce Enthusiast

Formulabruce

Posted
Posted

A friend had this problem and it ended up being a valet issue with a remote starter.

Good luck..

  • 1 month later...
1999 Z71 Enthusiast

1999 Z71

Posted
Posted

I am experiencing this now. Four days after we rebuilt our 6.0. Just like you ground checks, new crank and cam sensors. Hot and ground to coil plugs, no fire. Cant pull a code because it won't run. Any luck?

  • 4 months later...
Terry Norman New Member

Terry Norman

Posted
Posted
On 10/3/2020 at 8:14 PM, JHenline said:

I'm desperate guys. I've been searching and trying and implementing and testing for 3 days and I cannot figure out why I have no spark.  Working on a 2006 chevy 2500hd, 2wd with an LQ4 and 4l80e. I have crank, fuel, compression but no spark. What I've done so far
- verified <1 ohm resistance from each coil connector ground to battery negative terminal (brown wire) with key on and off

- verified battery voltage at each coil connector (pink wire) with key on
- verified pcm is sending signal for spark using data log in hp tuners when cranking

- checked and cleaned all grounds, all 4 wire harness to engine grounds, engine to battery ground, engine to firewall ground, battery to chassis ground, literally every ground I can think of and locate has been cleaned and reattached

- replaced all 8 ignition coils with known good coils from running engine

- replaced all 8 plug wires with known good wires from running engine

- replaced all 8 spark plugs with brand new ACDELCO iridium plugs

- deleted VATS

- verified good crank position signal by logging rpm while cranking in hp tuners

- checked and double checked all fluids, all full

Anybody experienced this and figured it out? Anything I have missed? I've been chasing this for 2 days now and can't figure it out. Any way to check pcm signal at coil connectors without a waveform scanner or fancy scantool?

Thanks for any input, suggestions, or help!

 

I Have a 2000 gmc 5.3l no spark issue also. Got gas coming out fuel rail but no spark at plugs

Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted

Just a shot in the dark but anyway to trouble shoot anti theft?  If that is triggered it wouldn't start.  Sorry I couldn't help more.

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