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Old 08-11-2013   #21
Pete
 
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Default Re: Something stupid??? I HOPE!!!

Before you go changing fuel pumps change out to the old ECM.

You mention that with the new ECM when you turn key on the fans go on
tell me ECM is bad or something wrong with the chip.

Pete
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Old 08-11-2013   #22
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Default Re: Something stupid??? I HOPE!!!

Hey Pete, unfortunately they took the old ecm as a core! Is there anyway to check if a ecm is good or bad?
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Old 08-11-2013   #23
WVZR-1
 
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Default Re: Something stupid??? I HOPE!!!

If you can recover your old ECM get it - regardless of your situation get the ECM core - pay the core value and hold it until the car runs. You shouldn't part with a core until you know you've received a "functional" good part.

I'd like to think it's not to late!

Post the part number from your invoice for the ECM that you purchased!!
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Old 08-11-2013   #24
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Default Re: Something stupid??? I HOPE!!!

Al,

Would he be able to even crank the motor if it was the VATS?
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Old 08-11-2013   #25
WVZR-1
 
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Default Re: Something stupid??? I HOPE!!!

Quote:
Originally Posted by XfireZ51 View Post
Al,

Would he be able to even crank the motor if it was the VATS?
The "fuel enable" aspect of VATS will allow "crank no start"!

I would seriously consider checking the CCM for faults. Either from a scan tool or just from the DIC module using this tool:

http://tech.corvettecentral.com/2011...trouble-codes/
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Old 08-11-2013   #26
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Default Re: Something stupid??? I HOPE!!!

Quote:
Originally Posted by WVZR-1 View Post
The "fuel enable" aspect of VATS will allow "crank no start"!

I would seriously consider checking the CCM for faults. Either from a scan tool or just from the DIC module using this tool:

http://tech.corvettecentral.com/2011...trouble-codes/
Referring to page 9D-2
there is no such mode as "crank no start".
Both fuel AND cranking are disabled together.
The CCM sees to it.

I submit, the problem at hand is not VATs related.
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Old 08-11-2013   #27
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Default Re: Something stupid??? I HOPE!!!

OK, marine lets nail this...........
Not sure where you're at with this but having another Z nearby that could come assist (parts swap) would be a GREAT advantage.
Anyone reading this from the Pacific Region that can chime in?

Short of that and after reading ALL of what you've written in the OP and all comments made up to now here is how I would proceed.
Forget INFL RST light. Forget Theft Deterrent issues.

1. If you can't get the original ECM back at least recheck all the connecters going into the ECM. Remove each and inspect for bent pins.
Also open the little cover on the ECM where the chip is installed. Check for pins not properly installed. Given no apparent issue you're going to have to proceed and assume the ECM is ok for now.

2. It would seem you have no fuel pressure at the rail but when you first flick the key on does it come up to about 50psi for a short time?

Staying with fuel for now can you connect a the pressure assembly and bleed off fuel repeatedly when you cycle the key on/off every 60 seconds?

Now, if you get an initial surge of fuel then nothing you could be looking at a failure in the primary pump but the secondary pump is fine.
At start both are on for 2 secs then only the primary is left to give fuel.
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Old 08-11-2013   #28
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Default Re: Something stupid??? I HOPE!!!

Quote:
Originally Posted by scottfab View Post
Referring to page 9D-2
there is no such mode as "crank no start".
Both fuel AND cranking are disabled together.
The CCM sees to it.

I submit, the problem at hand is not VATs related.
Fuel enable can be turned on or off in the PROM and is controlled by the signal from the CCM I believe. I won't debate the issue but yes there's a "fuel enable" and I believe the correct CCM code for it's failure might be 54. That's the primary reason I suggested going to the CCM to check for errors.

Adding to your items to check is maybe first of making sure the PROM is correctly seated in the ECM. That I might think of the most important starting point given all of the previous information. It might be wise maybe to post the information from the PROM - maybe it has someone's "autograph" on it. Maybe! Is it important? Likely not but it would be wise to note it.

Cranks but won't run is covered in 6E I believe and has it's own chart. I don't have a correct FSM but I'd guess maybe it would be A-3

OP - the code if it's an OE would be seen in one of the "windows" in the blue PROM cover on a silver label. Just note that information, it could become valuable later to you. Not for this issue maybe, but it will be of value I'd think.

You check first the things that you've done your self. The first thing you did when you replaced the ECM should have been to install the PROM - I'd start there. Just makes good sense!

Last edited by WVZR-1; 08-11-2013 at 01:10 PM.
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Old 08-11-2013   #29
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Default Re: Something stupid??? I HOPE!!!

Thanks so much for all the input guys! Unfortunately, as I am moving into my new base housing this week, I am going to have to wait until the weekend to continue on. The car is at my parents place in vegas, and I'm getting ready to head back to Cali shortly. So hopefully this thread won't die, because I really value all the input from you all! And Pete, I almost stood at parade rest when I read your post! Lol. But yes...ready and willing to nail this!! I would love to my wife to the Marine Ball this year in a ZR1 chariot!! So here's is the newest update for today. On the line of WZR1's thought train, I spent half the night doing research on the ecm I got yesterday, and low and behold I do believe the ecm they have listed as for the Z, is actually for a LT1! Last 4 of the part number is 7727. As far as I can see the pn for my car should be 16163993. This probably explains why with the new one, all of sudden my fuel pumps no longer engage, but my cooling fan sure as hell does! Thats what I get for making the rookie mistake of buying a ecm through autozone!! I really should have known better!! But the good news is, they still have my core, and I will pick it up on the way home today! Hopefully this other unit didn't fry my prom! Pete, since I will have the ecm and prom for a week, and no car...I will give the ecm and prom a good thourough examination. And I guess we can proceed from there! Do you think I should go ahead and order the correct ecm...or do you think there is a chance this could a non ecm related issue? Either way, this is going to be a long week waiting to get under the hood! At least she will be on a trailer coming back with me next week! This week is sofas and furniture!!! UGH!!! Thanks again guys!!!
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Old 08-11-2013   #30
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Default Re: Something stupid??? I HOPE!!!

As far as I know ECMs for the LT5 are NLA, so I doubt you could get one from autozone or any other car parts store.

Not unusual to get L98 or LT1 parts when you go to these places.

Lots of symptoms point towards the ECM, but as I was told, the ECM rarely fails.

You did mention SYS flashing, this is generally a weak battery. The ZR-1 is very sensitive to a good battery. My car was having strange issues that pointed to the ECM, but a new battery and all was good.
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