Spark/Ignition issue?
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From: Ashton, MD.
Do you still have an EGR? If so it could be stuck open a little which creates a big vacuum leak and all the big vacuum leak problems like rough idle and stalling.
I run manifold vacuum on my 460 and when the vacuum advance diaphragm on the dizzy went bad, in gear idle RPM dropped down to 525 ish but it otherwise idled and ran okay.
My stock 86 460 has the fuel pump in the tank. Hard to believe 15 PSI fuel pressure. I would think the carb would be running over! Stock fuel pressure is 8 PSI for a Holley but I think you need A little less for an Eddie.
I run manifold vacuum on my 460 and when the vacuum advance diaphragm on the dizzy went bad, in gear idle RPM dropped down to 525 ish but it otherwise idled and ran okay.
My stock 86 460 has the fuel pump in the tank. Hard to believe 15 PSI fuel pressure. I would think the carb would be running over! Stock fuel pressure is 8 PSI for a Holley but I think you need A little less for an Eddie.
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From: Ashton, MD.
Thread Starter
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From: Ashton, MD.
Mini update. Timing looks like it fine. Hard to tell exactly where it was but it was around 10.
I guess i need to find a way to check that fuel pressure at the carb to rule out a fuel issue. I bought a vacuum gauge as well so I’ll check that out soon. I have to admit after I did the rotor yesterday it seems better. Maybe it’s in my head but I do wish it idled a bit higher at times and adjusting the screws is really hit or miss.
I guess i need to find a way to check that fuel pressure at the carb to rule out a fuel issue. I bought a vacuum gauge as well so I’ll check that out soon. I have to admit after I did the rotor yesterday it seems better. Maybe it’s in my head but I do wish it idled a bit higher at times and adjusting the screws is really hit or miss.
Lead Driver
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Unless the EGR valve has an external leak, the spray test won’t do anything even if stuck open. It routes exhaust gas, not ambient air, into the intake manifold.
Probably the easiest method for testing is to unbolt it and make a sheet metal block off plate. Use the gasket as a template, but without the hole in the middle. See if it runs better then.
I’d also figure out that high fuel pressure. Don’t know if your gauge is wrong or the pressure is really that high. Not sure about the 460, but my ‘84 351W 2bbl is rated at 6-8 psi.
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From: Ashton, MD.
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From: Ashton, MD.
Just as a reminder, I have an electric in tank fuel pump that runs along the frame rail through the filter and on to a fuel pressure regulator at the front of the engine before going on to the carb. I would assume I need to test the fuel PSI before the regulator first to make sure the fuel pump is good? If that's correct what PSI should I be looking for?
If the fuel pump is good I guess I can then tie in again after the regulator to see if the regulator is the issue? If I had to put money on the issue I might put it on the regulator being the problem. What I really wanna do is just replace that and see what happens but I got scolded by yall last time for skipping diagnostics!
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From: Angier, NC
I did not read you whole last post but if it ran good to/from where you went but stalled backing into the parking spot I would say the filter is good (where I stopped reading ).
If it was starving for fule it will happen under load/ driving not at idle low load parking.
Dave ----
If it was starving for fule it will happen under load/ driving not at idle low load parking.
Dave ----
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From: Ashton, MD.
I did not read you whole last post but if it ran good to/from where you went but stalled backing into the parking spot I would say the filter is good (where I stopped reading ).
If it was starving for fule it will happen under load/ driving not at idle low load parking.
Dave ----
If it was starving for fule it will happen under load/ driving not at idle low load parking.
Dave ----
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From: Ashton, MD.
Update:
Slapped on a new fuel pressure gauge and it was running at about 7psi at idle in park. I adjusted the regulator and got it down to 5.5. Went for a short drive and the idle is much smoother. I think at this point is can play with the idle screw and moisture and MAYBE things will be in good shape. Will update.
Slapped on a new fuel pressure gauge and it was running at about 7psi at idle in park. I adjusted the regulator and got it down to 5.5. Went for a short drive and the idle is much smoother. I think at this point is can play with the idle screw and moisture and MAYBE things will be in good shape. Will update.
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From: Ashton, MD.
I realize this thread is running out of steam but my issue isn’t solve and I’m near the end of my rope with this thing. Below is what’s been done and a video of the BS still going on.
New: alternator, regulator, plugs, wires, cap/rotor, pcv valve, ignition module, ignition coil.
Tests: battery is strong, charging system fine at all rpms, vacuum reading was steady within .5 at 18.5, timing was just about at 10, fuel pressure at the carb set to 5.5 at idle with edelbrock 1406 carb.
Video was taken with warm engine. Park idle at 1000 and then immediately dropping 400-500rpm in gear. Foot on break and then wheel turn causing a stall out.
New: alternator, regulator, plugs, wires, cap/rotor, pcv valve, ignition module, ignition coil.
Tests: battery is strong, charging system fine at all rpms, vacuum reading was steady within .5 at 18.5, timing was just about at 10, fuel pressure at the carb set to 5.5 at idle with edelbrock 1406 carb.
Video was taken with warm engine. Park idle at 1000 and then immediately dropping 400-500rpm in gear. Foot on break and then wheel turn causing a stall out.
Post Fiend
Joined: Feb 2008
Posts: 5,831
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From: St Albert, Alberta
I realize this thread is running out of steam but my issue isn’t solve and I’m near the end of my rope with this thing. Below is what’s been done and a video of the BS still going on.
New: alternator, regulator, plugs, wires, cap/rotor, pcv valve, ignition module, ignition coil.
Tests: battery is strong, charging system fine at all rpms, vacuum reading was steady within .5 at 18.5, timing was just about at 10, fuel pressure at the carb set to 5.5 at idle with edelbrock 1406 carb.
Video was taken with warm engine. Park idle at 1000 and then immediately dropping 400-500rpm in gear. Foot on break and then wheel turn causing a stall out.
https://youtu.be/Dk8BWBMalF4
New: alternator, regulator, plugs, wires, cap/rotor, pcv valve, ignition module, ignition coil.
Tests: battery is strong, charging system fine at all rpms, vacuum reading was steady within .5 at 18.5, timing was just about at 10, fuel pressure at the carb set to 5.5 at idle with edelbrock 1406 carb.
Video was taken with warm engine. Park idle at 1000 and then immediately dropping 400-500rpm in gear. Foot on break and then wheel turn causing a stall out.
https://youtu.be/Dk8BWBMalF4