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Discussion Starter · #1 · (Edited)
I've had my intake off twice now in about a 4 month period and never had any issues with the fuel injector o rings. I replaced them all when I did the heater hoses, then I replaced the lower only when I did the expansion valve.

Today I'm giving the car a once over like I always do, and I noticed the number 5 injector o ring (going into the manifold) was just torn and disintegrated.... All the others look fine, and it wasn't leaking but that could have ended very badly if went unnoticed.

I used the injector kit (bought two sets) from LMR, so I either pinched it (likely the cause) putting it in or it was just a defective ring. Who knows, either way luckily I have spares and caught it.
 

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Did you apply some Vaseline or any other lubricant when you swapped in the new o-rings? It isn't a good idea to install them dry as they can get damaged in the process.
 

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I use ATF but nearly any lubricant will be fine.
 
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Did you apply some Vaseline or any other lubricant when you swapped in the new o-rings? It isn't a good idea to install them dry as they can get damaged in the process.
thanks for the tip.
 

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i just use clean motor oil on the o-rings and don't forget to clean the manifold ports before pushing in the injectors. I wrap the end of a plastic rod with a shop rag/cheap microfiber cloth with throttle body cleaner and gently clean out the port.
 

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Discussion Starter · #6 ·
I just changed the 4 out on the drivers side bank. I cleaned the injector tips real good, cleaned the bores real good and lubed with fresh mobil 1. This is the result...

So 8-7-6 look normal (that's oil that you see, it isn't leaking fuel) but 5 protrudes so deep you cant even see the ring? And I filmed the other bank as well. Those I put in dry. The rings on 6-7 and 8 had cracks in them and already started to dry rot. I'm ordering some motorcraft o rings for sure.

 

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They're not seated all the way. First, I know you probably already checked, but make sure that the old o-rings aren't still in the holes. That said, press firmly directly over the top of each injector until you feel it pop in. The front injector on the driver side looks to be the only one seated all the way. The o-ring sits all the down in to the bottom of the bore.
 

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Discussion Starter · #8 ·
Yes, no o rings where left in the holes. Interesting. Okay, I just put in the order for some new motor craft o rings, so I'll just yank them all off and replace all 16 of them.

They're not seated all the way. First, I know you probably already checked, but make sure that the old o-rings aren't still in the holes. That said, press firmly directly over the top of each injector until you feel it pop in. The front injector on the driver side looks to be the only one seated all the way. The o-ring sits all the down in to the bottom of the bore.
You weren't kidding, they "popped" in alright lol. I had to put quite a bit of force on the rail downward and sure enough, they all popped all the way in. I used fresh M1 when putting the rings on the rail and then I oiled the bore as well. All 8 100% seated now.

On a side note, I finally got my Steeda LCA's (Steeda 555-4417 Mustang Adjustable Rear Lower Control Arms (05-14)) installed too. Pretty easy install actually but 105 ft.lbs is no joke. I'm not exactly small but that was a work out. It didn't eliminate the wheel hop 100% but it was much more controllable and hopped much less. A few times it didn't hop at all. Gonna have to get the UCA to match it but overall, not a bad upgrade.
 

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Yea I've removed my injectors many times.The first time re-installing them was a bit nerve racking. Had 1 injector stay in the port and came out the rail the first time I removed them from the manifold.Thought I was going to break something putting them back in. I actually installed the Ford Racing 24lb 6 hole injectors a few weeks ago (they look like what you have installed; light purple/violet body). Surprisingly a set of 8 of those costs less than $200 whereas a set of 8 OEM Motocraft injectors costs $400.:rolleyes: I'll be sending my original out for cleaning and flow testing.
 

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Discussion Starter · #10 · (Edited)
Mine did the same lol. One of them pulled completely out of the rail the first time I took the rails off. As far as I know, these are the factory injectors. Everything on this car seems to be OEM / Motorcraft, as much bad luck as I've had with this car (A/C, clutch) at least it was well maintained with OEM parts.

Nice, $200 isn't bad at all. If one of mine goes I'll probably go that route. I did that with my new edge, one went then another went... Might as well just do all of them and be done with it.

That JLT catch can, is it pretty good? I'm tempted to grab one of them myself but the price... I noticed big time when I pulled the manifold that a lot of oil was getting sucked in and thought about grabbing one.

EDIT:

Oh and I spoke too soon the on the LCA's being not that noticeable. The first drive I had the windows down and didn't notice. This morning I went for a drive and holy gear noise lol. It's not unbearably loud but I had to speak up to talk to my passenger.

Reminds me of my 2002 tho. Rock solid, loud, squeaky but super fun to drive.
 

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If those injectors have 6 holes they are not stock. The stockers are only 2 hole sprayers. The Ford Performance injector part# is M-9593-LU24A which will be stamped on one side of the injector. If you have these hopefully the previous owner had it tuned for them as they are "high flow".
Yea heim joints offer no barrier to transmitting NVH from the diff.
 
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Discussion Starter · #12 ·
Do you know if these came stock on any model? This got me thinking because I'm still having a cooling fan issue. The low speed fan just has a mind of it's own A/C on or off. The last few weeks I haven't even touched the A/C but I noticed the low speed fan hardly ever comes on. It's always the high speed.

So, I'm 99% sure I have the 6 hole injectors. I remember looking at them putting the o rings on and telling my self to not get oil in those holes while putting the o rings on. With that said, it has to have a tune to even run them, yes? How can I tell if I'm on the stock tune?

It does have cats, no CEL or wrench and no codes using FORScan. It also passed an OBD2 emissions test as well if that helps any.
 

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To my knowledge all 4.6L 3v came with 2 spray hole injectors. Yes it will run with out a recal but since they are a higher flow rate, I believe the fuel trims will be way negative, but may be not to -25% to trip stuck rich codes.
 

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Discussion Starter · #14 ·
So... Would these 6 hole injectors even run with a stock tune? I seriously need to get in contact with the previous owner.

Speaking of which, assuming it is not the stock tune, how do I get the stock tune back?
 

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From what I researched, yes they will run on the stock tune but will not be optimized. In the link I posted above, Ford Performance provides the data to adjust the MAF and injector tables for tuners.
As for how to retrieve your stock tune (if you do indeed have a custom tune), you would either have to contact the previous owner to get the tuning device which would have downloaded the stock tune to itself and "married" the device to the vehicle and return it to the stock tune and "un-marry" the tuning device from the vehicle. Or you'll have to have a dealership reflash the PCM back to the stock tune. They use the reference code stickered on the PCM to know which factory tune it originally came with.
 
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