LS not firing in 86 C10

[shortboxin]

It was running great until I decided to install purdy aluminum valve covers with coil covers. Once I installed the valve covers, I discovered there was no good way to use the factory 2004 truck coils, so I bought a set of 8 Chinese 99 Camaro/Firebird coils and some harnesses to match on ebay.

Installed the coils and harnesess, but no start. Didn't even sound like any spark. Put a spark plug in the end of cylinder #1 and turned over, no spark

Found schematics indicating pinout for the 99 coil harness and from what I found everything matches to the PCM connector pins of the 2004 truck PCM. Per what I found on LS1tech, that there should be 5-7k ohms from the coil connector GND to output of the coil. Tested the coil from cylinder #1 and it's wide open. Tested my original truck coil from GND to output and it's just over 5k ohms.

Figured the full set of Chinese coils from ebay must be bad. Ordered a set on Amazon. Pulled the first coil out of the box and tested GND to output. Again, it's open.

Am I missing something or is every Chinese LS1 coil bad?

 

[Chevy 88]

Put one of the original coils back on that was working fine, and test that one.

 

[shortboxin]

I'll give it a try, but I'm pretty sure it will work fine.

Is there any way to ohm out the LS1 coil? I found this coil pinout which contradicts my harness as they would be inverse of each other (A would be D and so on). As you can see, the GND on my connector would align with pin D of the coil.

Can anyone verify that this coil pinout is correct or if my harness is backwards?

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[Ricko1966]

I'll give it a try, but I'm pretty sure it will work fine.

Is there any way to ohm out the LS1 coil?

Yep check primary resistance on your new coils with a multi meter. Compare it to old coils check secondary resistance Compare it to your old coils. Are your new coils grounded somehow? I'm not familiar with the LS coils but any other coil has a ground for the secondary side,usually through their mounting system. NM. Just read original post, in your 1st post you already checked secondary resistance and they don't check out. Send them back. Try to figure out how to make your old coils work,or buy local where you can check resistance at the parts counter.

 

[TotalyHucked]

A) I'm a little fuzzy on the details but I do know you can't just mix and match coils willy nilly, there's certain ones that will work with whatever setup you have and some won't. There's several different styles of coils for these engines and they don't all play well with truck stuff.

B) Pretty much all aftermarket coils are junk. To the point that most of us prefer to grab them out of the junkyard over ordering anything online, it's gotten that bad.

 

[shortboxin]

Thanks for the help guys. I looked further into the wiring harness and from what I see online for factory LS1 (Camaro/Firebird/Corvette) coils with harnesses installed, the harnesses I bought were wired backwards.

Literally, the +12V was wired to GND on the coils and signal + and - were reversed (see pic above). Rewired all 32 connections and it fired right up. Gave it gas and it revved up no issues. Never tested it under load though. That's for another day.