Car cranks but no spark or injector pulse

[willizm]

Hi all, we are trying to start up the t/a and are having spark and injector pulse issues. The car cranks fine, but there is no spark and it seems as though the injectors aren't spraying either. We tested the power off of the coil pack connecters and they are showing that we are getting 12v so I dont think it's a grounding issue. Also the fuel rail mechanical gauge is showing that we are getting 50+ Psi so I know fuel is getting there. I can here the fuel pump kick in. It just doesn't spray. What do you guys think it could be? I'm thinking maybe cam or crankshaft position sensors so we might switch those out. Any ideas?

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[Junk86]

Not positive but I think the cam sensor tells the injectors and coils to fire. You sure it didn't come unplugged when messing with it?

 

[willizm]

We took the intake back off and it looked like it was seated properly.

 

[02BlueGT]

Isn't the. Crank position sensor also used for fuel/ spark... Might want to check that

 

[Eagle]

Check the crank sensor...

I've read issues where the crank sensor didn't line up properly with the reluctor ring... Let's hope that's not the issue.

Also, run thru this no start diag:

http://www.hotrodlane.cc/New LS Links Page/Engine Cranks but Does Not Run.htm

 

[willizm]

Thanks Dan I much appreciate it. I'll give it a look and report back. Once this thing fires up then it's time to drive it around without a bumper for a week.

 

[Eagle]

I love that part (driving around without the bumper)!

Also, another good thread from TECH on troubleshooting wiring:
http://ls1tech.com/forums/conversio...-ls1-swap-checked-everything-i-can-think.html

 

[6literEat'r]

im having the EXACT same issue when i went to fire my beast up tonight

 

[Eagle]

 

[hellraiser319]

Oil pressure sender..? I know in some cases it will keep the engine from running if it doesn't see oil pressure to prevent engine damage. IDR if its the fuel pump it cuts on the GMs or otherwise...

 

[6literEat'r]

as i was cranking...i was able to watch my oil pressure gauge rise more and more with every crank

 

[6literEat'r]

WELL...got it started....dont know wtf i did, rechecked all my connections, unplugged shit, plugged it back in, ran a jumper from my gtp to the t/a and let it run to charge the batt up...and before it cranked like it had the power to fire, but didnt fire...
for no reason at all..it fired right up and had started every time since..id try getting a charger on yours for a while and try again.

 

[willizm]

got mine started too. Was the crank sensor and now she, errr, moves

 

[6literEat'r]

good deal mane!

 

[6literEat'r]

i got a new problem tho car will only start with my diagnostic scanner plugged into the obd2 port..lol i dont get it

 

[02BlueGT]

got mine started too. Was the crank sensor and now she, errr, moves

 

[Eagle]

i got a new problem tho car will only start with my diagnostic scanner plugged into the obd2 port..lol i dont get it

You sir have electrical issues.

 

[6literEat'r]

You sir have electrical issues.

im pretty certain that im having a pcm ground isse, and the ground eyelets are on the back side of the driver head, and i remember bolting them on, but the surface is dirty..

 

[Eagle]

That would do it...

 

[willizm]

Yeah, In the day I had my issue I read a good deal about issues with those grounds if they weren't in place specific to the pcm.

 

[6literEat'r]

problem solved..sorry didnt mean to "thread hijack" or anything, just posting about similar problems..

SOMEHOW one of the eyelets for a heavy duty pcm ground broke off, dont know if it was brittle or what, but i forsure bolted it on when re assembling..upon rechecking the ground today back there it was broken off...

fixed that ground, cleaned the mating surface up..car starts on its own power! w0oh0o

 

[willizm]

Nice, two resolutions, one thread, all win!!!

 

[6literEat'r]

 

[Boostie]

You guys come fix mine and eagles car now :csi:

 

[willizm]

Maybe there is a rule on tcg. Only 2 running turbo t/a's at a time




J/k