That’s what I run in mine. Last one ran but was low on base pressure, got worse under load. That was a spectra I want to say, I replaced it with a Delphi from Napa. So far so good.
CK5
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I've been running a Walbro in my tank for 12 years without 1 issue, so far. I have 3 of them in stock now if you need one. They are Made in the USA pumps. You couldn't get them for over a year it seems.
Sounds exactly like what's going on with mine. This is an AC Delco pump but I know they've fallen off the past few years. The crew cab had either Bosch or Delphi in the saddle tanks and never had a problem.
This afternoon I rerouted the fuel supply line so it's as smooth as possible. No change.
I think that's what I need to do. Might add the small Hydramat too for good measure.
That thought crosses my mind frequently. Even my wife made that same comment. But when it's good, it's so good. And it hasn't left me stranded, that would be the final straw.
That being said, I'm still having a problem with the PF4 completely cutting out randomly and for short bursts. I thought it was the fuel type, but now it's happened with the ethanol free. I've been slowly narrowing down the circumstances and I think it's gotta be picking up RFI from the PWM fan controller.
It's never acted up on the morning drive. It's cool enough in the mornings the fans never come on, even in the summer. Every time it's happened, the fans have been on. It's frustrating because it doesn't happen every time the fans run. Based on my experience with the glitchiness from the fuel pump not being on a relay, it seems plausible the current glitching could also be from electrical interference.
I'm really torn about it because I really like the controller. The soft start makes it so you can't even tell when they start running. Once they're going, they modulate to a steady state where the fans just run at a steady speed that maintains coolant temps. There's not the constant on and off of the fans cycling as the coolant temps rise and fall.
How many amp alternator do you have, and what's the charge wire size?
150 amp alternator. I have an 8ga wire from the alternator to the battery in addition to the factory connection.
The battery has both top posts and side terminals. The fans are on the side terminals with the factory connections, fuel pump feed, and the added alternator cable. The PF4 is connected on the top posts. I don't know if that really matters because the terminals are probably essentially one piece inside the battery. I also checked everything was tight just last night.
When this first started happening, I thought maybe the fuel pump was cutting out which was the motivation to install the in- tank pump. Since then, I've figured out it's the entire PF4 that's momentarily shutting off. I believe this because when it stalls I lose RPM signal.
The battery has both top posts and side terminals. The fans are on the side terminals with the factory connections, fuel pump feed, and the added alternator cable. The PF4 is connected on the top posts. I don't know if that really matters because the terminals are probably essentially one piece inside the battery. I also checked everything was tight just last night.
When this first started happening, I thought maybe the fuel pump was cutting out which was the motivation to install the in- tank pump. Since then, I've figured out it's the entire PF4 that's momentarily shutting off. I believe this because when it stalls I lose RPM signal.
The issue with interference is strange to me. Why are the aftermarket systems so sensitive to EMI when the factory based systems seem to be much better at dealing with it. I don't say that to have you switch on this truck, but I know both Mark and Dave had issues with their Edlebrock systems if they even tried to use a CB in the truck. I've had both a CB and HAM radio in operation in mine and not a glitch out of the factory ECM.
But I've read enough that if any of the aftermarket systems are not set up exactly as directed they have problems. I wouldn't expect your PWM fan controller to be an issue normally, but I think you did a good job of isolating the issue. I wonder if putting an RF choke on the power wire to your fan controller would help keep the EMI at a lower level where the Edelbrock system doesn't flip out.
Sounds like your alternator is good! I remember that now, although for a 150A I think I would use larger charge cable. Below is a chart from powermaster on alternator charge wires.
I remember a while back you had a melted wire, any way it wasn't just that one or you didn't get it all?
Also, I wouldn't hook the fan ground directly to the battery. I would hook it to the frame. This way, the ECU has a better ground path than the fans. The fans will still have a solid ground, but the fan motor PWM won't be directly at the battery.
One way to shield the interference is to spiral wrap a wire around the positive wire, and then ground it at both ends. However, if the issue is voltage drop, then this won't help. I also feel like this can cover up the real issue.
You need to determine how if the voltage is dropping, or if it's EMI. I have one of those pico scopes, it connects to a laptop via USB and is a good o-scope for not a lot of money, at least it used to be, everything is expensive now. I've used it to diagnose things on EFI with success. Its a very good tool I think I paid $100 for and I don't use it often, but when I do it's irreplaceable.
Can you watch the voltage the ECU sees when this happens? I suppose bluetooth might not be fast enough to see it, but you should see if it cuts out?
I remember a while back you had a melted wire, any way it wasn't just that one or you didn't get it all?
Also, I wouldn't hook the fan ground directly to the battery. I would hook it to the frame. This way, the ECU has a better ground path than the fans. The fans will still have a solid ground, but the fan motor PWM won't be directly at the battery.
One way to shield the interference is to spiral wrap a wire around the positive wire, and then ground it at both ends. However, if the issue is voltage drop, then this won't help. I also feel like this can cover up the real issue.
You need to determine how if the voltage is dropping, or if it's EMI. I have one of those pico scopes, it connects to a laptop via USB and is a good o-scope for not a lot of money, at least it used to be, everything is expensive now. I've used it to diagnose things on EFI with success. Its a very good tool I think I paid $100 for and I don't use it often, but when I do it's irreplaceable.
Can you watch the voltage the ECU sees when this happens? I suppose bluetooth might not be fast enough to see it, but you should see if it cuts out?
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Todd was telling me a thought he had about aftermarket efi. He was wondering if the factory manufacturers have a lot of the technology locked down with patents and the aftermarket is having to make the systems work by a round about means that isn't as robust. It's an interesting thought.
Looking back at this thread, I think I might just have a 100amp factory alternator. I think the 150 amp alternator I saw in my purchase history went in the crew cab.
I think you had mentioned the fan grounding before but I had forgotten. I was just thinking someone had given me an idea on the fan wiring to give the EFI priority but I couldn't remember what the details were.
I will try that ground change and the spiral wire wrap to see if it helps. It would be nice to keep the fan controller.
I was thinking voltage drop could be an issue. Usually the stall happens at speed so the alternator is spinning high enough to be at the rated output. I've only had it stall on me once while stopped.
Another weird aspect is that it will stall 3 or 4 times over a short time and then never happens again for the rest of the drive.
My dad has been in the auto chip industry for the last 45yrs. I can guarantee you that the OEM’s have much more stringent testing and certification than anything aftermarket. They can’t afford failures. You imagine how upset the public would be if their vehicles randomly died because their electric fans turned on?
They also only test systems designed by one large OEM. They don't test anything made by another manufacturer because the combinations are endless.
Yes and no. The same chip could be in 20 different oem’s. So the chip manufacturer tests it to their spec, sells it to the oem’s, then they test it to their spec, and back and forth.
I don't think its a patent thing because they have been shielding stuff for decades. Utility patents only last 21 years. And sheilding stuff was primitive, either actual shielding, see below, or filters like capacitors, inductors, etc.
The OEM does a lot of testing. I have been where they were doing testing when I lived near Detroit. You had to leave the chamber, with the vehicle inside running. I said why? The answer "because if you are in there when we turn on the electrical signals it will kill you!" I thought, why does the vehicle have to keep running if the driver is dead? Perhaps it won't kill you immediately? Anyway my point is, they test very thoroughly.
They also have super expensive multi channel oscilloscopes, heck 15 years ago they were $30,000 for one scope. I used to work on the "ignition team" since we sold cam and crank sensors to the OEMs. So sometimes if there was in issue at a specific plant I would have to grab the scope and go to the plant and hook everything up and find the problem with the vehicle.
However, one thing the OEMs can do that the aftermarket can't, and this is likely a huge issue for the aftermarket. Is they can wire it exactly how they want, and it will be that way every time. And they can test it thoroughly to make sure it works. There is a myriad of ways electrical issues can pop up, even if a person wires it very professionally, the order and location of connections can have a huge effect. They can prevent ground loop issues by attaching grounds for different things certain distances from the battery. They obviously do twisted pairs on speed and position sensors, and shield them, , this is just the tip of the iceberg. The aftermarket can do some of these, but they don't know how long the power and ground wires are in the vehicle, and how many other things you have hooked up and where, and what runs parallel to what, they have no control over that. If you run important wires parallel to plug wires for example, it can definitely cause issues because high voltage and high current stuff is much more likely to cause these problems. And low voltage stuff like 5V sensors are more susceptible to interference.
You want to know what the temporary check was if there was a failure in that test? Cover things with aluminum foil. They could wrap the offending sensor with aluminum foil and bam, problem solved. Then you knew what to fix, whether it be the sensor itself or the wiring. But that only prevents airborne noise, not noise coming from the electrical system itself, like voltage fluctuations, etc.
The OEM does a lot of testing. I have been where they were doing testing when I lived near Detroit. You had to leave the chamber, with the vehicle inside running. I said why? The answer "because if you are in there when we turn on the electrical signals it will kill you!" I thought, why does the vehicle have to keep running if the driver is dead? Perhaps it won't kill you immediately? Anyway my point is, they test very thoroughly.
They also have super expensive multi channel oscilloscopes, heck 15 years ago they were $30,000 for one scope. I used to work on the "ignition team" since we sold cam and crank sensors to the OEMs. So sometimes if there was in issue at a specific plant I would have to grab the scope and go to the plant and hook everything up and find the problem with the vehicle.
However, one thing the OEMs can do that the aftermarket can't, and this is likely a huge issue for the aftermarket. Is they can wire it exactly how they want, and it will be that way every time. And they can test it thoroughly to make sure it works. There is a myriad of ways electrical issues can pop up, even if a person wires it very professionally, the order and location of connections can have a huge effect. They can prevent ground loop issues by attaching grounds for different things certain distances from the battery. They obviously do twisted pairs on speed and position sensors, and shield them, , this is just the tip of the iceberg. The aftermarket can do some of these, but they don't know how long the power and ground wires are in the vehicle, and how many other things you have hooked up and where, and what runs parallel to what, they have no control over that. If you run important wires parallel to plug wires for example, it can definitely cause issues because high voltage and high current stuff is much more likely to cause these problems. And low voltage stuff like 5V sensors are more susceptible to interference.
You want to know what the temporary check was if there was a failure in that test? Cover things with aluminum foil. They could wrap the offending sensor with aluminum foil and bam, problem solved. Then you knew what to fix, whether it be the sensor itself or the wiring. But that only prevents airborne noise, not noise coming from the electrical system itself, like voltage fluctuations, etc.
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That's kind of true. They OEM doesn't make the ECU, the sensors, the wiring harness, etc. They build the engine in house and assemble the car with parts from 1000s of manufacturers. And they test them all together, and make the manufacturer test them to a spec the OEM decides on many instances. So they do both in a way.
Our sensors had to be tested so many different ways it was funny. We had to heat them up to like 300 degrees and then dunk them, while running, into like 20 different fluids. saltwater, oil, spray paint, etc. If the thing was hot and suddenly cooled, it could pull in the fluid, if it leaked. If not, it would pass. Then they would be put in a autoclave, and super high heat and humidity, for weeks straight. And monitored for errors the entire time.
Once they passed all this, then the entire vehicle testing would commence. They have hot rooms, cold rooms, EFI rooms, sound rooms, wind tunnels, etc. One time I walked from a hot room that was like 120 degrees to a cold room that was 10 below zero in just a dress shirt, that was a shocker! Then they would take the vehicles to places like death valley for hot inclines and Sault Ste Marie, MI for cold testing in the dead of winter.
I'm mainly talking about the OEM side of the testing. They have very few configurations for a large number of vehicles to test. They test it to death with a large budget relative to an aftermarket supplier. While an OEM supplier may hasn't multiple customers, the OEM level testing will find most of the system level issues and chase down how to fix it before going into production.
An aftermarket supplier could never test every possible combination for every possible vehicle their product will be used for.
I agree
I watched a video on YouTube with a guy having trouble with his FiTech system cutting out and acting strange. They ended up melting the epoxy off the computer board to investigate and found wires that were stripped back too far and touching, and terrible soldering. The rest of the video is the guy bashing FiTech for their customer service. It's on the Fuzzy Dice Projects channel, if you want to see it.
I know you run a ProFlow but I just wanted to bring this up. If I remember right you sent it back in to have it serviced?
I know you run a ProFlow but I just wanted to bring this up. If I remember right you sent it back in to have it serviced?
I did end up sending the ECU in. This is actually a replacement ECU. Man, I hope it isn't something like that. It would be nice to have a spare ECU to swap in and test to see if the problem persists.
It wasn't the ECU the first time and I doubt it's the ECU this time. The ECU is rarely the problem with the quality systems like Edelbrock, Holley, FAST, BS3, etc. I don't include anything that puts the ECU on the throttle body in that statement.
Including GM PMDs from the 90s...
