I have read almost every single thread on ih8mud about the Holley Sniper Install. Can't seem to figure out now, why the car cranks, but won't fire! Someone help! Thank you
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Yes, Truck ran before the Sniper install. The battery is good. Fuel pump is getting 58psi. I do have spark, and I have not messed around with the timing.Did the truck run prior to the sniper install? Is your battery good? How did you setup the fuel pump and system. Is 60psi getting to the Sniper? Do you have spark and correct timing? Did you setup the Sniper Wizard correctly? Are there any areas that you could be getting wiring interference?
Do you see an RPM on the display while it's cranking?Yes, Truck ran before the Sniper install. The battery is good. Fuel pump is getting 58psi. I do have spark, and I have not messed around with the timing.
Sniper Wizard setup is as follows:
Engine Displacement: 420
Set Idle Speed: 720
Isn't the displacement in cubic inches? 4230cc is 258.13 cu.in by my calculationsYes, Truck ran before the Sniper install. The battery is good. Fuel pump is getting 58psi. I do have spark, and I have not messed around with the timing.
Sniper Wizard setup is as follows:
Engine Displacement: 420
Set Idle Speed: 720
Good catch!Isn't the displacement in cubic inches? 4230cc is 258.13 cu.in by my calculations
Sniper Wizard setup is as follows:
Engine Displacement: 420
Set Idle Speed: 720
Can confirm. These things run rich out of the gate.All jokes aside. The Holley system probably starts up richer than the required stoichiometry 14.6:1, as richer AFR's mean lower cylinder temps (insurance for Holley). That's mass of air/mass fuel (AFR). Add the base "rich" mixture to your input parameter for displacement as 420 in^3, and your almost 2 times the mass of fuel for the air than the 2f is sucking in at a given rpm. In other words, your "flooding" the system. The air is the limiting reactant here. You need to input the correct parameter for your specific displacement to correct your AFR. Once you do this it may start, or at least you can move on to checking other things.
Did you set the engine displacement for Sniper wizard at 260? There are no decimals to put in exact engine placementIsn't the displacement in cubic inches? 4230cc is 258.13 cu.in by my calculations
what should I set the engine displacement parameters to?The 420 is what did it. I think your so stoned, you tried to start your couch.
Can you go 258? Otherwise 260 should be close enoughDid you set the engine displacement for Sniper wizard at 260? There are no decimals to put in exact engine placement
Ignition timing.Got to work on it today, Finally fires, but wont stay running. Any ideas!>
How long does it run for?Got to work on it today, Finally fires, but wont stay running. Any ideas!>
Doesn't even stay running that long. RPM shows STALL. Just sputters, then shuts off.How long does it run for?
Is it showing your RPM on the handheld display?
What is your A/F mixture reading while it is running?
The reason I ask, is if it's not getting an RPM signal from the coil, you'll get a prime shot and a sputter, but no run.
If it's running (or trying) rich or lean, that will show up on the display.
I suspect you're not getting an RPM signal to the Sniper from the coil. Its sputtering from the prime shot but without an RPM signal it will never continue to inject fuel. Stock ignition system? Correct yellow wire to the negative side of the coil? (I think there are 2 yellows)Doesn't even stay running that long. RPM shows STALL. Just sputters, then shuts off.