2000 LS1 in a 68 Camaro -She was running. Drove to the gas station & I shut her off. Wouldn’t restart. Has no trouble codes. Got her home. Had fuel pressure - had no spark. No trouble codes. I replaced the crank sensor and then she started & then I shut her off & now she won’t start again. No trouble codes and I can’t get her started.
What do you think? Suggestions? Comments? Thanks in advance.

 

Check ALL electrical connections and grounds.

 

Yes...checked & double checked...

 

Checked all six coils- no spark. Checked all my fuses- I’m good -checked my relays -check good.

I went to check power at my harness connection to my coil packs. It is still the stock set up. I was curious to know what I should have on each color wire going to my coils -harness -for each side ?

 

SIX coils?????

 

You should be getting roughly 12 volts at the coils. With your replacement of the CPS, it really soulds like an issue to do with that. It will cause issues like this. Check the wiring to the sensor, at both ends. I had an issue with mine where I only got spark on 4 cylinders, randomly because I used a sensor that was not AC Delco. Swapped it our for an AC Delco one and it fired right up. I believe I had an ICT Billet one before because it was slightly cheaper. I would look at this with more details as I believe that's probably where you issue is.

 

Try disabling vats

 

Typo...8 coils

 

Tried that too

 

Thanks- I did change out the crank sensor with an Aldelphi brand but still nothing

 

Reposting again! Please help! Stumped. All these views and no new suggestions??

2000 LS1 in a 68 Camaro -Daily driver. Drove to the gas station & I shut her off. Wouldn’t restart. Has no trouble codes. Got her home. Had fuel pressure - had no spark. No trouble codes. I replaced the crank sensor and then she started & then I shut her off & now she won’t start again. No trouble codes and I can’t get her started.
What do you think? Suggestions? Comments? Thanks in advance.

New crank sensor, disabled vats, checked & double checked all electrical connections, relays, etc.

Stumped 🤔 Please help.

 

Do you have injector pulse?
If you've got no spark or inj pulse then you were on the right track with the crank sensor.
My next move would be to plug in a scanner and see if it reads engine RPMs when cranking. If it doesn't the signal isn't making it to the PCM.
I'd want to see cam pulses too. Not everyone has a lab scope though.
Do you have 12V to the coils and injectors while cranking?

Joe

 

Fuses? Just throwing it out there even though you said you checked relays, etc.

And you can have fuel pressure, but the injectors not be pulsing. I always pull the fuel rails (it's easy to do) and put a piece of card board underneath it and then crank the engine to see if the injectors are actually spraying fuel

I've also seen a couple times issues where the grounding locations behind the heads become a little loose causing issues, but you may have check that. Make sure they are real tight.

 

Even if you have 12V TO injectors/coils, they are activated by GROUNDING thru the ECM.
So if there is a bad connection after the live 12V feed, you would still not fire.

 

A data log while cranking?

 

I took everyone’s advice and I checked the voltage of the coils and at the crank sensor. At first I didn’t see voltage of the crank sensor and then I did. I put everything back together and I took apart some connectors and reconnected them. She started right up. Took her out for a ride, shut it and then she started right back up again. Fingers crossed she might be fixed. Thank you for the support out there!

 

Glad it's running...but it's not fixed...

 

No start... Anyone have any ideas what this problem can be? I am open to any and all suggestions. Thanks in advance.

 

From what I read it seems you went over where the problem was. Just not knowing exactly where. I would go over everything again inspecting for any kind of flaw in anything. Mainly wiring/connections of coarse. Got some good help in here. Good luck man.

 

I would try wiggling the wires around the crank sensor and have someone see if it starts. I bet its a loose wire into crank sensor or a bad wire in harness. Ive seen this around trans area. Especially after trans install and trans pinches harness.