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Old 07-19-2024, 06:00 PM   #1
Shifty One
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Re: Sniper EFI + Dual Sync - No Spark (was a driving truck)



Did they mention potential reasons for the failure?
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Old 07-25-2024, 08:46 PM   #2
RustyPile
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Re: Sniper EFI + Dual Sync - No Spark (was a driving truck)

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Did they mention potential reasons for the failure?
X2.. That question screams to be answered.. I hear/read this complaint about Holley not offering a flow chart or diagnostic procedure for their Sniper systems. "well, it sounds like the XXX is broken"... Every experienced mechanic knows that guesswork is not a diagnostic procedure..

KyleSeal, did the Holley Rep offer any steps that will verify his guess prior to buying another ECM??
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Old 07-26-2024, 08:10 AM   #3
KyleSeal
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Re: Sniper EFI + Dual Sync - No Spark (was a driving truck)

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Did they mention potential reasons for the failure?
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Originally Posted by RustyPile View Post
X2.. That question screams to be answered.. I hear/read this complaint about Holley not offering a flow chart or diagnostic procedure for their Sniper systems. "well, it sounds like the XXX is broken"... Every experienced mechanic knows that guesswork is not a diagnostic procedure..

KyleSeal, did the Holley Rep offer any steps that will verify his guess prior to buying another ECM??
The rep himself did not really offer any extra means to diagnose - but as you can see I did do quite a bit myself before calling.
I think the warning signs for me were an erratic IAC, and killed an O2 very early on.
The main 'diagnosis' that lead me to believe the ECU failed is that the white wire, when grounded, will create a strong spark at the distributor. Since the Sniper controls spark when using a dual sync distributor, this would indicate either a dual sync dist issue, or a Sniper issue, and since the handheld shows RPM when cranking, indicates the Sniper is at fault.

But - come saturday, I will have the Sniper 2, and will update if it runs at that point.
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Old 07-26-2024, 01:54 PM   #4
Shifty One
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Re: Sniper EFI + Dual Sync - No Spark (was a driving truck)

Your Sniper I wasn't that olde, was it?
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Old 07-29-2024, 08:15 AM   #5
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Re: Sniper EFI + Dual Sync - No Spark (was a driving truck)

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Your Sniper I wasn't that olde, was it?
As far as being used, no, about a month of consistent run time. As far as purchase, I bought it in 2022. I really should have waited so I could have had a warranty while it was running but at that point I wasnt sure of my road with the truck, so I got it to get the expense out of the way. All I did was incur another cost at a later date
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