Injector Noise
I have no gauges, etc, I can't tell you much else other than the repairs listed in my public record doc above - here's 3 cell phone videos, if they don't suffice, I could break out the GoPro:
1) Idle Driver's side front wheel well: https://drive.google.com/file/d/0B73...it?usp=sharing
2) Idle w/ low RPM using accelerator - passenger side back wheel well (turbo / exhaust): https://drive.google.com/file/d/0B73...it?usp=sharing
3) Placed under the hood 0-30MPH 1500-2000 RPMs: https://docs.google.com/file/d/0B73i...lUeFR2WTg/edit
Notes:
- 2002 Ford Excursion w/ the legendary 7.3 Powerstroke / ~236k miles (35" tires and speedo was never calibrated, so guessing it has maybe close to 250K on these injectors) - all other information can be seen via my public record doc here:
https://docs.google.com/spreadsheet/...0E&pli=1#gid=0
- I bought the truck in Oct 2013 with ~226k from the original owner, who's not very helpful unfortunately :-/
- MPG are ranging from 14-18 MPG based on conditions, etc. This seems normal since I have 35" tires and a 4" lift. Truck is all stock but the Hutch mod.
- To start, I've always heard a very light high-pitched tick at idle, and assumed it was the infamous #8. I came to this conclusion from reading random posts stating this injector tends to be noisy but I'm confused on what's an okay noise vs what's bad

- For the first time, I can here the knock/ticking noise from inside the cab, specifically from 0-30MPH with low RPM (1500-2000). Mostly, it's the loudest when starting in the morning (sitting over night) or when I head home from work (again, truck sitting, getting "cold"), until the truck warms up, it seem to be much less noticeable. If I'm in a hurry and only let the truck run for a few mins, then it's the loudest, and it appears plugging in the block heater helps, but it's currently been 50-80 degrees, so I shouldn't have to plug it in!
- Could be my imagination, but I believe it began being louder (heard from the cab) after my OEM fuel pump died, and I let the truck quit running on it's own (basically running out of fuel), rather than turning it off immediately - I was on the highway during rush hour, and was trying to get to my safety - almost got rear-end!
- When driving, if you let off the accelerator, the tick/knock goes away, at least being able to hear within the cab
- I originally thought the BF1212 fuel filter from the Hutch mod was lowering fuel pressure, hence causing louder injector noise - changing the filter didn't make any noticeable difference via my "ear test", and changing my oil (Mobile 1 5w40) at the 4500 mark to Mobile Delvac Super 1300 (15w40) allowed for improved acceleration, but made no difference with this "noise".
- Fuel Additives: SeaFoam in the fuel bowl trick seems to make a huge difference, but I can still here a light, high-pitched tick at idle, just not from the cab. SuperTech 2-cycle oil doesn't seem to really make a bit of difference as it relates to the tick - not 100% sure yet, just add about a 100 mile ago. I've also been running Stanadyne's lubricity formula, which also doesn't seem to make a difference with the light tick. To clarify, all seem to help quite the engine, but not resolve this tick/knocking.
- Oil Additives: To scared to try this route, and there just doesn't seem to be many 7.3 folks proclaiming a must do
Most importantly, I want to determine if I can continue to drive the truck since it's my daily or do I need to park until I can afford the repair. Yes, I can take it to the shop, and ask them, but hey, I like the idea of asking my "peers" first!
It could very be that they are tired and/or nearing the end of their life. But there's nothing you can do about it. There is absolutely no reason to drive it. That would be like buying a new car and being afraid to drive it because it might get scratched! You could potentially try RevX or Archoil in the oil to see if the chatter improves. I wouldn't try any off the shelf auto zone oil additives.
Maintenance is key. Keep up and it will live as long as possible. Drive on brother.
The ticking... that's a tough one to get rid of, if it's not an exhaust leak. Look for soot anywhere under the hood - soot does not belong under the hood. If no soot, the ticking is likely the solenoids. Knocking can be addressed, but ticking is frequently the activation of the solenoid. The plate comes up and smacks the solenoid coil base - and this makes noise without the truck even running.
Once you add hundreds or thousands of PSI of oil pressure, the ticking can get pretty loud. I listened to your video and the truck sounds normal through your microphone - with the camera placement you had. Injector knocks are heard under the truck, behind a front wheel.
Some injector knocks involve replacing the injector - like the one in the video. There are more subtle knocks that can be addressed with fresh O-rings and a good injector torqueing. I've done all of the above, and other relevant mods are in my signature.
What makes the knocking sound come and go? Seems like it would happen all the time or none at all.
Before aiming for sticks, I made certain they had proper care and feeding.
I had one brand new injector bang away, and I swapped it out to quiet the truck down. I can't emphasize enough how twitchy those things can be.
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BTW....I just switched to Mobil 1 synthetic, and have only a few thousands miles since the last oil change. Seems as though I just started to hear this knocking stick after the switch. Coincidence?
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When I isolated the problem to #7 cylinder, I made a test harness that I could switch on and off each individual injector. If I shut off #7 the sound goes away. No other injector makes a change in sound. If I pull my foot off the accelerator above 50 mph and all the injectors quit firing, the noise goes away. Because of this I know it is an injector and not a mechanical noise.
I checked out the entire Exhaust Back Pressure System - nothing wrong.
I tried a known good IDM - no change.
I checked out the wire harnesses and found nothing wrong - no change.
I tried a known good PCM - no change.
I checked the exhaust system for leaks - no leaks.

I picked up a rebuilt engine during the recent Economic Depression with the intent of driving this engine until it quit.
I have put 40,000 miles on the truck and it still runs fine, except for the noise. The odometer is pushing 306,000.I may give up and install the other motor just because I'm tired of listening to the knock!
And everyone stares at me when I drive by. And I have to shut down the engine to order at a drive-through. And I have to turn up the radio to hear it. And I can't hear anyone on my hands-free speaker phone. And the people I call can't understand me because of the knocking noise drowning out my voice. 
The new engine has forged rods, too. I might add a tuner to that one.
https://www.ford-trucks.com/forums/9...oring-pic.html
Also, I've been switching between the SuperTech and Stanadyne's lubricity formula, and SuperTech just works better as it relates to quieting her down + it's cheaper and easier to find.
Anyhow, I still hear the "tick" at idle, but that just seems to be the norm with these old dawgs.
Onward through the fog!











