Edelbrock Proflo 4

[mrk5]

I have used an Android app called "ScreenCam" that does that pretty well, you can even add the audio from the phone mic if you want.

From the looks I wonder if you are losing spark temporarily?

Also, I put the same gasket back in in the exact same orientation Edelbrock installed it (you can see the imprint from the throttle body).

About this whistle, did you guys install a turbo and not tell anyone?

Seriously though, does it actually whistle or is it more like a tiny air leak sound from the throttle body? Can you duplicate the whistle at 30% throttle in neutral, or is it only under load? If so can you temporarily place something over the IAC inlet hole to plug it and see if it goes away?

If you can duplicate it in neutral it would be very helpful as you could try to find it then.

I've never heard any type of actual "whistle" in any of my testing the last few years, so I am curious to find out where it is coming from. I am guessing the throttle plates or IAC valve.

Make sure your intake manifold bolts and throttle body nuts are snug. I always check the manifold bolts each time it cools off the first few heat cycles.

I kinda figured you would have just put the original gasket back. I wish it was forced induction.

I can't replicate it parked because 30% throttle is screaming. I did look at the secondaries versus TPS and it looks like they open somewhere near 60%.

Here's a video I recorded of the whistle. Not sure how well the phone mic catches.

It's not a deal breaker issue, so it's on the back burner for now until I figure out the random dying issue.

Fuel pressure could play a big role if you are seeing inconsistent numbers. What version are you on?

Also, what fuel pump are you running and how is the fuel line and fuel return ran? I assume your fuel pressure is at 43psi with the vacuum line off and plugged.

It updated the firmware with the initial setup. The little box in the lower right corner of the E-turner app says v4.0.1:7, firmware: 65.

So I decided to try starting from scratch. I re-ran the setup wizard. I'm not changing any of the parameters. The default idle is 750 RPM, and I just adjusted the idle speed screw enough to get the IAC at 13% - 15%. I also pulled the vacuum and double checked fuel pressure. It was running about 42.5 so I dialed it up 43.5; I was aiming for 43 but figured an extra .5 was okay because the vacuum thingy lowers it back anyway.

I have 2 reasons for doing this. First I was thinking maybe some of my tweaking with idle, timing, and AFR had things all wonky. Second, I thought maybe there's a possibility the map didn't load correctly.

If it's still dying on me, I'll have to call tech support. That was the recommendation on the Edelbrock forums. Aside from that, they must all hang out with @Bent77 because other than the moderator everyone just focused on the 500 RPM target idle.

 

[mrk5]

Fuel pressure could play a big role if you are seeing inconsistent numbers. What version are you on?

Also, what fuel pump are you running and how is the fuel line and fuel return ran? I assume your fuel pressure is at 43psi with the vacuum line off and plugged.

Fuel system info is near the bottom of this post: https://ck5.com/forums/threads/1973-c10-the-purple-truck.331985/page-37#post-4127791

I did recheck the fuel pressure with the vacuum disconnected. Technically it ended up at 43.5.

 

[folkenheath]

I kinda figured you would have just put the original gasket back. I wish it was forced induction.

I can't replicate it parked because 30% throttle is screaming. I did look at the secondaries versus TPS and it looks like they open somewhere near 60%.

Well that should been obvious to me, of course you can't go 30% throttle in neutral, unless you are doing a major rev limiter test, ha ha. At first I was thinking try to duplicate it and then I saw the 30% and just threw them together without thinking.

This dying issue sounds electrical in nature because it is intermittent. Your fuel pressure looks well within the expected range for driving at low load.

I have looked at the video several times, and it appears immediately before it died the TPS suddenly dropped to zero throttle. Did you do that? Or did it just think you did that? If it did that while you were at steady state throttle I would be checking the TPS to make sure it isn't lose or a faulty connector, etc.

 

[Bent77]

I kinda figured you would have just put the original gasket back. I wish it was forced induction.

I can't replicate it parked because 30% throttle is screaming. I did look at the secondaries versus TPS and it looks like they open somewhere near 60%.

Here's a video I recorded of the whistle. Not sure how well the phone mic catches.

It's not a deal breaker issue, so it's on the back burner for now until I figure out the random dying issue.


It updated the firmware with the initial setup. The little box in the lower right corner of the E-turner app says v4.0.1:7, firmware: 65.

So I decided to try starting from scratch. I re-ran the setup wizard. I'm not changing any of the parameters. The default idle is 750 RPM, and I just adjusted the idle speed screw enough to get the IAC at 13% - 15%. I also pulled the vacuum and double checked fuel pressure. It was running about 42.5 so I dialed it up 43.5; I was aiming for 43 but figured an extra .5 was okay because the vacuum thingy lowers it back anyway.

I have 2 reasons for doing this. First I was thinking maybe some of my tweaking with idle, timing, and AFR had things all wonky. Second, I thought maybe there's a possibility the map didn't load correctly.

If it's still dying on me, I'll have to call tech support. That was the recommendation on the Edelbrock forums. Aside from that, they must all hang out with @Bent77 because other than the moderator everyone just focused on the 500 RPM target idle.

I’ll speak with Dave for you since you have a phone allergy

 

[Kain]

the main guy at edelbrock tech line said stay out of wizard it is only for new setup, and you need firmware update should be v65

 

[folkenheath]

The only thing is, if someone made a mistake at initial setup, or used the wrong tune, never going back could be leaving a better setup on the table.

 

[Shawn]

I posted the Edlebrock upgrade video showing how to do the v65 upgrade in this thread.

Also, should that external pump should be gravity fed? I know they can picky if you use a suction tube. I ran into this issue with a Edelbrock low pressure pump and had to modify the tank and add a fitting at the bottom of the hot rod so the fuel flows into the pump feed. For EFI setups I prefer in tank pumps or a low pressure in tank to feed external fuel pump. Not saying this IS the problem but something to question. I'd also check for any bad electrical connections or a possible bad relay thats driving the pump. Also, maybe try running with the cap loose to make sure there is enough venting.

From Walbro's site:
-Must be mounted below fuel tank for proper fuel feed to pump
(Edelbrock pump is a Walbro)
Please note that this is a pusher style fuel pump and must be mounted below the fuel tank and as close to the fuel tank as possible. Failure to follow these installation instructions will result in the pump to prematurely fail which is not covered by warranty.

I know its close, but its not below tank. Maybe a problem, maybe not. Could it cause a problem with fuel pressure? Not sure. Just a question I'm asking.

 

[Bent77]

I kinda figured you would have just put the original gasket back. I wish it was forced induction.

I can't replicate it parked because 30% throttle is screaming. I did look at the secondaries versus TPS and it looks like they open somewhere near 60%.

Here's a video I recorded of the whistle. Not sure how well the phone mic catches.

It's not a deal breaker issue, so it's on the back burner for now until I figure out the random dying issue.


It updated the firmware with the initial setup. The little box in the lower right corner of the E-turner app says v4.0.1:7, firmware: 65.

So I decided to try starting from scratch. I re-ran the setup wizard. I'm not changing any of the parameters. The default idle is 750 RPM, and I just adjusted the idle speed screw enough to get the IAC at 13% - 15%. I also pulled the vacuum and double checked fuel pressure. It was running about 42.5 so I dialed it up 43.5; I was aiming for 43 but figured an extra .5 was okay because the vacuum thingy lowers it back anyway.

I have 2 reasons for doing this. First I was thinking maybe some of my tweaking with idle, timing, and AFR had things all wonky. Second, I thought maybe there's a possibility the map didn't load correctly.

If it's still dying on me, I'll have to call tech support. That was the recommendation on the Edelbrock forums. Aside from that, they must all hang out with @Bent77 because other than the moderator everyone just focused on the 500 RPM target idle.

Yeah I figured the engineers at Edelbrock set the factory parameters for the idle at 750 just to piss you off

 

[imiceman44]

I did some searching and found some others that had similar whistling problems...

https://forums.edelbrock.com/forum/pro-flo-efi/pro-flo-4/31943-any-recalls-for-components-yet

https://forums.edelbrock.com/forum/pro-flo-efi/pro-flo-4/33327-iac-and-whistling

So I read all of the thread and it appears intake gasket is to blame for the whistle which is what some already suggested and I believe could also causing the erratic behavior.
I think it's worth checking.

 

[Bent77]

So I read all of the thread and it appears intake gasket is to blame for the whistle which is what some already suggested and I believe could also causing the erratic behavior.
I think it's worth checking.

It may be the IAC doing the whistle, he said the vacuum readings were between 16 and change to 22.

 

[imiceman44]

It may be the IAC doing the whistle, he said the vacuum readings were between 16 and change to 22.

They say that the IAC is a common sound but not whistling. I guess I should listen to his video to see if it's whistling or hissing like the IAC.
I did hear that sound on some of my vehicles but it's clearly not a whistle.

 

[mrk5]

Well that should been obvious to me, of course you can't go 30% throttle in neutral, unless you are doing a major rev limiter test, ha ha. At first I was thinking try to duplicate it and then I saw the 30% and just threw them together without thinking.

This dying issue sounds electrical in nature because it is intermittent. Your fuel pressure looks well within the expected range for driving at low load.

I have looked at the video several times, and it appears immediately before it died the TPS suddenly dropped to zero throttle. Did you do that? Or did it just think you did that? If it did that while you were at steady state throttle I would be checking the TPS to make sure it isn't lose or a faulty connector, etc.

I was thinking it's so hard to tell exactly when it dies and what's happening just before or after. Really need to be able to hear the engine better to know for sure. I downloaded an app called XRecorder to capture a video of the screen. I only chose it because it had the highest rating of the search results. Hopefully using it will help.

I’ll speak with Dave for you since you have a phone allergy

Honestly last night I was tired of thinking about it. I woke up at 3:30AM this morning and couldn't STOP thinking about so you should have called then.

I posted the Edlebrock upgrade video showing how to do the v65 upgrade in this thread.

Also, should that external pump should be gravity fed? I know they can picky if you use a suction tube. I ran into this issue with a Edelbrock low pressure pump and had to modify the tank and add a fitting at the bottom of the hot rod so the fuel flows into the pump feed. For EFI setups I prefer in tank pumps or a low pressure in tank to feed external fuel pump. Not saying this IS the problem but something to question. I'd also check for any bad electrical connections or a possible bad relay thats driving the pump. Also, maybe try running with the cap loose to make sure there is enough venting.

From Walbro's site:
-Must be mounted below fuel tank for proper fuel feed to pump
(Edelbrock pump is a Walbro)
Please note that this is a pusher style fuel pump and must be mounted below the fuel tank and as close to the fuel tank as possible. Failure to follow these installation instructions will result in the pump to prematurely fail which is not covered by warranty.

I know its close, but its not below tank. Maybe a problem, maybe not. Could it cause a problem with fuel pressure? Not sure. Just a question I'm asking.

Yeah, I don't think it's below, but just right at level with the bottom of the tank. Right now I think it should be okay because I have a full tank of gas.

It doesn't seem to struggle at all. It's pretty quiet; I can hear the in-tank pump in our 2008 Silverado more than I can this one. I videoed my screen last night so it's easier to watch what the system is doing and I saw it get as high as 42psi the one time I accelerated moderately hard. If it's causing me trouble, I think it's a faulty part like it's dropping power randomly or something.

I would have preferred an in-tank pump, but I couldn't find a TBI sending unit anywhere in the U.S. That goes for pickup or blazer/burb TBI tanks. I think the only way you can find one is if you get lucky and find a local parts place with one in stock.

 

[mrk5]

They say that the IAC is a common sound but not whistling. I guess I should listen to his video to see if it's whistling or hissing like the IAC.
I did hear that sound on some of my vehicles but it's clearly not a whistle.

It does sound like the IAC on my Sniper. It made a similar noise when I first install the Sniper, but it was far more prevalent; basically any time I was opening the throttle.

After restarting the setup wizard and setting it up with the 750RPM idle and keeping all the setting a default including time and fueling, the throttle position where the noise starts is now at about 25%. It may also be a little quieter. The IAC is also running much different percentages, so I think the noise is related to IAC.

 

[mrk5]

After restarting the setup wizard, I had a lot more trouble. I think this is because you can't realistically expect your vehicle to run properly without at least doing some changes to the system - namely timing.

I set the idle speed screw so that it idled at the default 750 RPM with the IAC varying between 13% to 15%. I noticed on my test drive the IAC was generally operating at a much higher percentage at all times. Sometimes I saw it way over 50% open. I also felt like there were times I could hear it opening even though the screen said it was unchanged; I could even feel the engine pulling like I was accelerating.

One side benefit; this morning at 30°F, it started and stayed running without throttle input. When I put it in gear it did not die. So that was an improvement.

For my next test, I'm going to try adjusting the distributor advance to where I would normally run it. I want to see if maybe this will decrease the need for the IAC to maintain idle. One thing I find interesting is the Sniper will park the IAC above a certain throttle position, but my PF4 does not. Depending on those results, I might readjust the target idle so that the IAC is at the bottom end of the scale. I've also debated about getting a helper and seeing what happens if you set the IAC with the transmission in gear.

Something I learned in the re-reading of the instructions last night; I will reset the self-learn after making the target idle adjustments. I did not do that last time.

I will also recheck the plug connection for the IAC and TPS.

I really like to try and figure stuff out for myself. So I want to try a few more things and when I get to a point I'm out of ideas, I'll contact tech support. Before I do that, I'm hoping I can at least pin down some more concrete info on what's happening when the truck dies on me.

 

[folkenheath]

Maybe I heard you wrong, but two suggestions:

1: Once you "sync" the distributor with the ECM, don't move the distributor. Make all changes in the Edelbrock app under "spark control". Here is what I would put in there to start if I was doing the setup with your engine...(after syncing using the "Base Timing" icon)
Idle 20 degrees at 800 RPM
Total 34 @ 3000 RPM
Vacuum Advance: Max it out (15 as of this post)

The vacuum advance only goes up to 15, and that's at 30 inHg. No engine I know of produces 30 inHg so you will never even see 15, I run 16 degrees of advance with only 8" of vacuum with my vacuum can. I think Edelbrock needs to up the range on that so you can set the timing at 34-38 degrees at WOT and still achieve 50-52 degrees at low load cruise. If the software allows this in the future this is what I would shoot for with a conventional head SBC or BBC. I may speak with the Edelbrock engineers about this.

2: Instead of changing the target idle RPM to achieve IAC %, move the throttle screw to achieve the target IAC% at the target idle. Then key it off and restart it to "rezero" the IAC back to zero at the new idle throttle position. I'm guessing the throttle blades need to be opened more for the new higher idle RPM to lower your IAC % back down when the engine is warm.

 

[mrk5]

Right, I'm not moving the distributor itself. And yes, I did mean adjust the throttle speed screw.

I wanted to up the vacuum advance but I wasn't sure if I should. So you have given me vindication there. I live at 5000ft elevation, so I usually run advance a little higher than common suggestions. That said, I think the first time I set everything I had idle timing too high because I didn't realize there was a vacuum advance feature.

One question I haven't looked for an answer to yet; does it add vacuum advance at idle? In other words, are they treating vacuum advance like it's connected to a ported or manifold source?

 

[6872xtc]

I haven't reset the self learn after making idle changes. Hell I have changed the idle speed on the trail while the kid was driving, let it learn it. Done it several times to find what works, I typically will raise the self learn RPM up to 1100 after I let it learn, it saves it from try to learn how to handle lots of playing with the throttle while crawling along. Bumping the throttle a lot confuses it, especially with the A/C going.
I just check the IAC percentage after playing with idle speed and timing to se if I need to correct the throttle opening. Typically don't have to touch it.

 

[6872xtc]

Let me say it this way, I do most of my idle speed changes on my phone, I don't touch the set screw unless the IAC gets out of range. This isn't a carburetor.
And yes, the timing will affect it all, of course.

 

[folkenheath]

I realize this isn't a full on 16x16 or 32x32 grid to set timing, however, this single number for the vacuum advance could be greatly improved if they made it just two numbers. One number for the "max vacuum advance" meaning a limit to hit it won't go above, and then another number for the ramp rate, like 1 deg/inHg or something. This way, if you wanted to, you could be all in by 8 or 10" if ones cam doesn't produce much vacuum at idle, and it still wouldn't go above the max amount at cruise. This would also allow tuning the vacuum advance to almost any engine combination by changing the max and/or the ramp rate.

As for the vacuum advance at idle, I would surely hope it would be active at idle, what is your timing shown at idle(hopefully more than your set idle timing)? It would be nice if they had a check mark for that (active or not active at idle). Most applications would want it active at idle unless its for emissions testing or something.

 

[Shawn]

Gotcha on the tank/sending unit. I didn't have any problems on my new TBI sending unit but that was a year ago. I do need a new tank since my baffle is loose so thats going to suck if they are out of stock. Might be able to find something used on car-part.com.

I'd keep on eye on the fuel pressure when it starts acting up since it appears thats when it has issues and drops in the low 30s.

When I called Edelbrock tech (you have to wait) and put my name and number down, one of the knowledgeable tech's called me back and had me input all the values they suggest. This helped me tremendously and it ran great after that even on the dyno with some minor timing tweaks. I'll have to go back and see what those numbers were but this was a SBC and I know you you have a big block. Don't leave your number to be called back. For some reason that doesn't always work.