View Full Version : Pro Flo 4 on a Blueprint 347 SBF from Forte's Parts Won't Fire
I'm building a MK4 with a 347 purchased from Forte's Parts. I tried to fire it up today and got nothing. It cranks, but no fire. I've got fuel pressure and the plugs appear to be firing. I tested a couple with a tester and the old fashioned way with a screwdriver. I removed the #1 plug and brought it to TDC on the compression stroke and the distributor rotor is pointed to the #1 wire. I double checked the firing order. I even put a couple of squirts of carburetor cleaner down the throttle body to see if it would fire. No luck. That kind of surprised me. It sort of feels like it's way out of time or not getting fuel at all. The Edelbrock app indicates everything is fine. I'm new to the Pro Flo 4, so any suggestions are welcome. I'm going to check everything over before calling Forte's on Monday.
gbranham
08-09-2025, 04:48 PM
Did Mike run it on the dyno before sending to you? If so, have you removed the distributor since that dyno run? I have ProFlo4 on my 427, and it was pretty straightforward.
egchewy79
08-09-2025, 04:49 PM
You have air, fuel and spark. I suspect your timing is way off.
Nigel Allen
08-09-2025, 05:09 PM
Is the distributor installed 1 revolution out of sync?
A friend of mine ordered a 302 just like mine and received it from Forte earlier this year, installed it and had multiple issues from the beginning. The thermostat housing leaked, the pressure regulator leaked and wasn’t properly set, no video or dyno sheet (both of which he paid for), and no Sniper tune loaded and he had to start with the wizard from scratch. It really seemed like they just threw parts on it and shipped it out.
I got my 302 from Forte about a year ago and it was perfect. All accessories were well attached, had a dyno sheet of it after being tuned, well calibrated tune on the Sniper, no leaks. I just dropped it in, hooked it up and it ran great. I don’t know if their previous engine builder quit or they got a new person to assemble the engines after mine or just rushed through my friend’s build, but his experience with Forte’s Parts was very different than mine.
Just FYI.
Did Mike run it on the dyno before sending to you? If so, have you removed the distributor since that dyno run? I have ProFlo4 on my 427, and it was pretty straightforward.
It was run on the dyno, I've seen the video. I haven't taken anything apart or removed the distributor or anything like that. That's why I'm so perplexed. All I did was run the wiring harness and hook everything up. It's really weird.
Is the distributor installed 1 revolution out of sync?
It doesn't appear to be, that's why I'm confused. With the #1 cylinder at TDC on compression, the distributor is pointing at the number 1 plug wire.
A friend of mine ordered a 302 just like mine and received it from Forte earlier this year, installed it and had multiple issues from the beginning. The thermostat housing leaked, the pressure regulator leaked and wasn’t properly set, no video or dyno sheet (both of which he paid for), and no Sniper tune loaded and he had to start with the wizard from scratch. It really seemed like they just threw parts on it and shipped it out.
I got my 302 from Forte about a year ago and it was perfect. All accessories were well attached, had a dyno sheet of it after being tuned, well calibrated tune on the Sniper, no leaks. I just dropped it in, hooked it up and it ran great. I don’t know if their previous engine builder quit or they got a new person to assemble the engines after mine or just rushed through my friend’s build, but his experience with Forte’s Parts was very different than mine.
Just FYI.
Yeah, there were a couple of weird things. When I starting putting everything together, the throttle body was loose, one of the pins in the idle air control valve was bent (I was able to straighten it), and today I realized the harmonic balancer bolt was finger tight.
A couple of thoughts. 1st I'd put a timing light on it. Assuming the ecu is controlling timing it could be something in setup. They may not have even run it with your ecu, so go through and check all your setup parameters. Also, verify the fuel pressure is correct. Check to make sure you're seeing rpm on the ecu.
Bob
A couple of thoughts. 1st I'd put a timing light on it. Assuming the ecu is controlling timing it could be something in setup. They may not have even run it with your ecu, so go through and check all your setup parameters. Also, verify the fuel pressure is correct. Check to make sure you're seeing rpm on the ecu.
Bob
That's a good point. I was assuming they had set up the ECU, but they may just plug in another ECU.
gbranham
08-09-2025, 08:38 PM
Assuming you made all the ProFlo electrical connections, are you sure the injector harness connections are on the correct side of the engine? They're labeled #1, #2, etc....make sure injector connection #1 is on the front cylinder on the passenger side.
And are you using an ignition box? If so, tell us how its wired. You may be getting spark, but is it at the right time?
gbranham
08-09-2025, 08:57 PM
today I realized the harmonic balancer bolt was finger tight.
What the heck?
gbranham
08-09-2025, 09:01 PM
You might go back through the setup Wizard in the ProFlo app, to have it load a fresh base tune. Also, you can turn your key on, engine off, connect to the ProFlo app, and it'll tell you if it is communicating with all the sensors. Might be good to look at, as a sanity check that everything is plugged in properly.
217426
No MSD, just a Pertronix coil. I was getting frustrated this afternoon. Tomorrow I'll go back at it from the beginning.
One thing, are you sure you are at base 12 degrees BTDC? for the PF4 to work properly you must be at base 12 degrees. If this is not set correctly nothing will work. I am running the PF4 and it fired right up on my first start. You can also call the Edelbrock tech line and they can help you out.
If you do go back through the startup wizard make sure you save the current tune setup so you can refer back to it later. It might be helpful to see where they put certain settings like AFR targets, timing tables, etc...assuming they did all that. If they did it might be a good reference point later, if they didn't then you haven't actually lost anything. (I'm a Holley Sniper guy so I'm assuming you can save the current tune like you can on a Holley.)
Starting over again with the startup wizard might be helpful. Greg did that with his engine and likes the way it's running. Just do what you have to do to get it going and you can tune on it later, or even use the current tune again later (assuming there is one) once you've eliminated any variables and got it running .
One thing, are you sure you are at base 12 degrees BTDC? for the PF4 to work properly you must be at base 12 degrees. If this is not set correctly nothing will work. I am running the PF4 and it fired right up on my first start. You can also call the Edelbrock tech line and they can help you out.
I expected it to start right up, but it's kicking my butt. I've confirmed the timing it at 12 degrees. There's plenty of fuel pressure. I ran the setup wizard again. Nothing. Doesn't even spit and sputter. It's really odd. Guess I'll wait 'til tomorrow and start by calling Forte's and then maybe Edelbrock if necessary.
cv2065
08-10-2025, 11:30 AM
Sounds like something simple just overlooked. Check your inertia switch? Make sure all of your wiring is right. I forgot to re-hook up the power to my MSD box while adding an amplifier lead to the battery and had one of those WTH moments when it would just crank but no fire.
The finger tight balancer bolt wouldn't sit right with me though.
Sounds like something simple just overlooked. Check your inertia switch? Make sure all of your wiring is right. I forgot to re-hook up the power to my MSD box while adding an amplifier lead to the battery and had one of those WTH moments when it would just crank but no fire.
The finger tight balancer bolt wouldn't sit right with me though.
The inertia switch cuts power to the fuel pump which seems to be working fine. I agree it's something simple that I've overlooked.
gbranham
08-10-2025, 02:38 PM
A little more info on the fuel injector harness plugs. They're labeled "INJ#R1" through R4 on the passenger side, and "INJ#L1" through L4 on the driver's side. Be sure to check this.
217445
gbranham
08-10-2025, 02:42 PM
And when you cycle the key and hear the fuel pump, what does the ProFlo app read for fuel pressure? It should jump to 58-65PSI if you're plumbed properly.
217446
And when you cycle the key and hear the fuel pump, what does the ProFlo app read for fuel pressure? It should jump to 58-65PSI if you're plumbed properly.
217446
It is about 65 psi and the app diagnostics indicate it's "green".
gbranham
08-10-2025, 03:58 PM
It is about 65 psi and the app diagnostics indicate it's "green".
That's good. Sounds like your fuel system is plumbed properly. Check that off the list. How about your injector harness connections? I'm in the shop now looking at my ProFlo setup, racking my brain for ya...
Greg
Mike.Bray
08-10-2025, 06:26 PM
Are you giving switched power to the ProFlo with the Orange wire marked Coil/EFI? This wire stays at full voltage during cranking which is important. Using another switched wire won't work, don't ask me how I know.
Are you giving switched power to the ProFlo with the Orange wire marked Coil/EFI? This wire stays at full voltage during cranking which is important. Using another switched wire won't work, don't ask me how I know.
LoL, I'll check it.
Are you giving switched power to the ProFlo with the Orange wire marked Coil/EFI? This wire stays at full voltage during cranking which is important. Using another switched wire won't work, don't ask me how I know.
You're talking about the orange wire marked "coil or EFI" in the Factory Five wiring harness I assume? I'm not sure what it would connect to. The Edelbrock harness has a wire to the ignition switch and a wire to the positive battery terminal. What would the orange wire connect to?
gbranham
08-10-2025, 07:47 PM
The orange "Coil or EFI" wire in the RF harness needs to connect to the red/black wire in the ProFlo harness. If it's not, that may be your problem.
The orange "Coil or EFI" wire in the RF harness needs to connect to the red/black wire in the ProFlo harness. If it's not, that may be your problem.
I'll give it a shot.
gbranham
08-10-2025, 08:13 PM
I'll give it a shot.
Look at my build thread, starting on post #177.
cc2Arider
08-10-2025, 08:19 PM
The orange "Coil or EFI" wire in the RF harness needs to connect to the red/black wire in the ProFlo harness. If it's not, that may be your problem.
That's how I wired mine...and while I haven't started it yet, I did check that it will have power during cranking too (checked about 5 different times with a multi-meter) :p
Craig C
egchewy79
08-10-2025, 09:57 PM
Are you running the clutch safety switch? My version of the manual had it wired up incorrectly. Switching the wires got mine to fire up
gbranham
08-10-2025, 10:26 PM
It cranks for him, so I assume its wired correctly.
rich grsc
08-11-2025, 07:43 AM
I agree, must be wired wrong at the switch? I needs to be wired to both run & start, sounds like it's wired to run only.
I knew it was going to be something stupid. Apparently, unbeknownst to me, Forte's puts a solid plate between the throttle body and intake manifold to prevent crap from getting in there. I certainly understand that, but they also taped a big cap over the top of the throttle body for the same reason. I have the chassis up on a dolly and I can't easily look straight down the barrels. I suggested they add a "Remove Before Starting" tag to the plate, lol. ;)
HA! Yes, they do that. Wish I had thought to tell you, but the fact that you cant open the throttle is probaby a good giveaway...
Was that it? You got it running now?
HA! Yes, they do that. Wish I had thought to tell you, but the fact that you cant open the throttle is probaby a good giveaway...
Was that it? You got it running now?
That's just it. The throttle plates opened all the way no problem. Apparently there is enough clearance even with that plate there. Lesson learned I supposed. It's running now, but I have a fuel leak where the return line connects to the fuel pump return. I'll probably have to replace that fitting.
Rian_Colorado
08-11-2025, 12:03 PM
I'm a week or 2 from being at the same point. Everything on my motor from Forte looks good, but I would NEVER have known this without this thread! I actually JUST noticed 2 days ago that the carb bolts were loose - really not even finger tight. I'm guessing that this is why (I'll have to remove them to remove the plate?) a "heads up" would have been nice though!
gbranham
08-11-2025, 12:52 PM
Congrats! Check for fuel leaks on the passenger side fuel rail, front corner, where the fuel pressure sender lives. Mine leaked pretty badly after a few heat cycles. It needed a few turns to tighten it, and its been fine since.
Anything that heat cycles will need checked and potentially tightened 1-2 times. Especially coolant clamps, fuel fittings, exhaust bolts, etc. After they've been through some heat cycles and withstood enough vibration you can start to trust they are not going to back off again.
I couldn't open the throttle on the Sniper with the plate in the way, I guess the throttle blades are positioned lower down than the Proflo unit. The Sniper blade are on the very bottom, much like a carb.
Maybe Forte assumes if you're knowledgeable enough to install an engine then you will figure out about the blockoff plate sooner or later. It's not like having it there is going to hurt anything. :)
gbranham
08-11-2025, 02:25 PM
Rarely is a no-fire caused by lack of air, lol. Usually fuel, spark, or timing. Funny.