Our first DTC P0308

[GT Pony]

I took the vacuum actuators and sensors off the back to see what broke and it was actually a metal rod. I was surprised and a bit disappointed. I expected the failure to be something that was made out of plastic. Go figure.

Wonder if the metal used in the rod is pure crap, or the rod cross-section just too small. I can't imagine it would take much torque to open the butterflies. Maybe they get jammed up/stuck for some reason and the torque ends up snapping the rod. Not all intakes do it, so maybe there was a crappy batch of metal rods made along the line (??).

Was there any indication that the mechanism was hard to move, any lack of lubrication or rust on anything?

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[Locksmith]

The flaps free and clear. A little dirty but easy to move.

If I had to guess, I'd say the flaps have their absolute open and close position but the vacuum actuator and lever have a longer travel. Repetitive opening and closing puts stress on the rod. If the rods are crap, they'll probably always break right there.

I looked at both ends of mine with a scope and it looks like the fracture started at a corner, deformed just that corner, and snapped clean all at once. I tried to get close up pics but almost impossible with what I have available.

 

[Cobra Jet]

It's back together and running with no CEL or DTC's. That was actually a really easy job. Have to have a torque angle gauge if you're going to follow Fords torque specs. But otherwise, all I needed was a set of new gaskets and well... a new freaking intake. Good luck with that if you want stock. National backorder from Ford. I found one on FB for $100.

I have verified with my old intake that if you have an endoscope and you remove the throttle body, you can get the endoscope up the intake runners and see if the flaps are moving or not. It's difficult to move them manually with the intake installed so I'd suggest a vacuum pump.

I took the vacuum actuators and sensors off the back to see what broke and it was actually a metal rod. I was surprised and a bit disappointed. I expected the failure to be something that was made out of plastic. Go figure.

With a working IMRC I did the air/fuel test again and got the same results.

The intact side and the broken side.

That's definitely a manufacturing OR supplier defect and IMO, anyone with an S550 5.0 that experiences that defect out of warranty period should be dutifully compensated for the entire repair including any labor+parts.

That's BS, period.

To me, IMO, the "rod" is way too small if it's being used in a fashion where pressure is exerted upon it MORE SO in such an a location where it's being articulated not just daily, but at numerous intervals while driving.

Also to note the IMRC system has been a POS design since its inception in the 1993 Lincoln MKVIII with the 4.6 DOHC, which that engine design then carried over into the 1996+ SVT Cobras, which it was still a shit design and was problematic with failures.

Eventually the Mustang aftermarket came up with 4.6 DOHC IMRC-delete plates which eliminated the potential for IMRC breakages, but if running N/A the con was that there was some lower end torque lost.

I don't know if an IMRC-delete would have the same effect (low end torque loss) on a Coyote or not since the power bands and drivetrain gearing are completely different vs prior S197/SN95 V8 platforms.

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Back to your images of the failed intake and IMRC rod....

I could be wrong, but it looks like corrosion also played a part in the rod breaking as there seems to be rust on the outer perimeter of the chamber as well as some inside where the rod assembly is inserted. No or yes? Hard to tell from the pics.

Can you open the intake to see where and how that rod protrudes through to the inside as far as how it's connected?

I wonder, are all of the Coyote 5.0 IMRC breaks centered at the same location as yours - meaning the rod is the 100% failure point?
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I see a potential for a fix, but if anyone designs it and patents it - please be sure to include me in on your profits or say 5% in perpetuity and mention of the inventor...

So here's my fix, outside of what I mentioned above that would be to redesign the part using a thicker diameter actuator rod.

The factory actuator rod is square. Looking at the part that is outside of the chamber where the rod broke, take THAT part and mill the end so it now has a female square. You're essentially making a "key" that once finished would now be inserted OVER the broken end of the rod in the chamber. Once the part is placed back over the rod, (and only if necessary) use some type of washer or loaded e-clip that would keep the exterior part from backing off the rod.

If something like that was designed, it would eliminate the excessive R&R for repair on an otherwise perfect intake... and cost far less in total $$$.

 

[Locksmith]

Getting a clear picture of the inside of the lever side is really difficult. I tried but nothing was good enough. It's not rusty. It may be some corrosion from the metal lever contacting a brass sleeve? Different metals will corrode but usually only when electricity is involved. It could also be discoloration from manufacturing. I can't get it apart so it may have been spot welded.

I planned on cutting the intake apart but now that you mention the repair, I'm pretty sure I'll keep it if the replacement breaks also. Your idea got me thinking and I believe I have a much easier repair in mind. One could simply fill the cup on the lever side with an exact amount of JB Weld or Marine Tex, line everything up where it's supposed to be, and install the lever. The inside square shaft would displace just enough epoxy to surround itself but not spill out. Secure the lever and hang the intake so gravity keeps the epoxy from oozing out while curing. Sorry bout your 5%.

 

[Cobra Jet]

Getting a clear picture of the inside of the lever side is really difficult. I tried but nothing was good enough. It's not rusty. It may be some corrosion from the metal lever contacting a brass sleeve? Different metals will corrode but usually only when electricity is involved. It could also be discoloration from manufacturing. I can't get it apart so it may have been spot welded.

I planned on cutting the intake apart but now that you mention the repair, I'm pretty sure I'll keep it if the replacement breaks also. Your idea got me thinking and I believe I have a much easier repair in mind. One could simply fill the cup on the lever side with an exact amount of JB Weld or Marine Tex, line everything up where it's supposed to be, and install the lever. The inside square shaft would displace just enough epoxy to surround itself but not spill out. Secure the lever and hang the intake so gravity keeps the epoxy from oozing out while curing. Sorry bout your 5%.

Good idea w/ the JB! It might work, but even with the smallest amount of JB or similar substance, the possibility exists for oozing and if it does, the actuator would be definitely seized and done.

Since you have the damaged unit/intake, give it a whirl and see what happens. It’s good tech and would definitley be helpful to others. If it does work, then you can either sell the intake as fixed or keep it for when the other IMRC fails.

 

[Locksmith]

Wanted to let you know the JB worked. Filled up the cup about half way and held it in place with a couple rubber bands while it cured.

 

[Cobra Jet]

Wanted to let you know the JB worked. Filled up the cup about half way and held it in place with a couple rubber bands while it cured.

That’s good to hear that a “JB” fix will benefit others too!

Any pics of the final repair?

 

[Locksmith]

The thing is back in the thing. Looks like nothing ever happened.

 

[TexasRebel]

Heck, I'd throw up just trying to carry JB to the checkout counter.

If the actuator is trying to twist the rod after full open/close, the actuator needs an overrun buffer spring.

 

[Mcgyver]

My intake just broke in exactly the same way. 23,000 kms on the car and the intake needs replacing - outrageous.

don’t think JB weld will help and Ford wanted to replace all coils, plugs and injectors before they would even consider the intake as the issue. That’s about $6,500 here in Oz.
Has anyone got a warranty claim on this from Ford as the intake is an outrageous $1,650 new from the aforementioned manufacturer.
Thought about a 2018 but that is even more expensive.
Grrrrrrrrrrrrrrrrr!

 

[GT Pony]

don’t think JB weld will help ...

In post #21 @Locksmith said it worked. If he's still here, maybe can chime in with an update if it's still working or not.

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