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Junior Member
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28 Posts
Discussion Starter #1
I currently have 195k on the odometer with original trans and injectors. Over the past several weeks I noticed a slight haze at idle but didn’t think much about it as the mornings have been relatively cool and humid. Last night, I noticed a slight loss of power and a tapping/chugging noise that at first I was attributing to an exhaust leak. Getting off the highway and under street lights I started smelling unburnt fuel and then I saw I was blowing smoke like a steam engine. At idle it also developed a rather loud fuel knock.

AE showed that I had a Cylinder #8 contribution error stored. Running a cylinder contribution test it showed all good, with 6 slightly down and 8 slightly down from that, but no complete failure to contribute. At this point, it still starts, but it is running extremely rough, all gauge reading are good, fuel pressure, ICP etc., the only thing slightly out of spec is my EGT which is roughly 100 degrees higher than normal, which I assume would be expected with an injector over fueling and dumping raw fuel.

I have not lost any coolant and it is clean, I also have no fuel in my crank case. My theory is injector 8 is stuck partially open, and it took 6 with it. My plan for the weekend is to do a compression test to make sure I didn’t melt/break anything, which I am hoping is true since 6 and 8 are still producing power. If that passes, replace 6 and 8 and keep my fingers crossed.

My question, does my assumption of what is going on sound on track, and does my plan to troubleshoot the problem sound correct? Any other suggestions on what to look for etc.

Thanks in advance.
 

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Curmudgeon
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472 Posts
I had very close to the same issue at the beginning of the year, maybe it's a common Tinton Falls vortex issue. In the end the problem was solved with two repairs.

The first was changing the EGR valve. It looked fine and tested fine, but a Ford truck service manager who I know well said even though the EGR tests and looks good, at the dealership they found replacement often solved the issue. He was partially right.

I still had a reduced amount of smoke and AE kept showing no issue, including the contribution test which with AE is only done compensated. I ended up getting a Ford IDS system and as soon as I ran the injector test uncompensated an injector showed a serious problem. Also looked at the output with the IDS compensated and the graph was balanced. So our trucks computers due a good job of adjusting output, but they can only do so much especially at startup. Remember that engine controls work best with a fully warmed engine.

I would agree that 6 and 8 are related, either by an injector internal fault or o-ring issue. And hopefully you're catching it before the other injectors on that bank are hurt.
 

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Junior Member
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28 Posts
Discussion Starter #3
It must be the Tinton Falls Vortex, or we buy fuel at the same station!

I will also check my EGR. I honestly haven't had it out for years.

I wasn't aware that AE was only doing a compensated test. That certainly explains my results. I was looking at picking up an IDS off of ebay, I guess I should have gotten one rather than just thinking about it.

Thanks for confirming I am on the right track. If I don't get rained out this weekend, I will post an update as the whether I am replacing two injectors or a motor.
 

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Curmudgeon
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472 Posts
I had it pulled out and it appeared fine. I had a spare on the shelf so it was an easy swap.

I understand the feeling. Before I tested with IDS I started looking at salvage motors.
 
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Junior Member
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134 Posts
I had a miss in mine and my brother hooked up his AE and it showed good so I took it to dealer and had a cyc contribution test and #1 inj was dead. I heard others say AE dose not do cyc test very good.
Ed
 

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Senior Member
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3,051 Posts
Without question you have an injector or two stuck open or a cracked nozzle dumping untimed fuel into the cylinders (fix immediately, do not drive the truck if you can). A stuck open or leaking injector can lead to a hydrolock situation or burn a piston up, when a faulty injector starts directing fuel away from the combustion bowl on top of the piston and towards the edge of the piston and cylinder liner that's when bad things happen to the piston.

Be sure to check your secondary fuel bowl pressure or install the blue spring fuel pressure regulator upgrade, low fuel pressures below 45psi contributes to alot of the fuel side injector failures, I have seen many running around the 25psi range because the regulator spring is worn, this hammers the inside of the injector as there is not enough fuel pressure to provide a fill cushion to the injector. With the blue spring upgrade you will have 65psi average pressure.

Harry
 

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Junior Member
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28 Posts
Discussion Starter #8
Just a quick follow-up. Last weekend I managed to tear everything down and the injector tips were intact which was a promising sign. The worst part of that job was removing the glow plugs from the passenger side (BTW, the engineer at International that decided to make a non-pliable metal bar for the glow plug harness on 2003’s should made to do cab-on head bolt repairs for the rest of his career). I ended up pulling the fender liner and it was still a pain. I only tested compression on the driver’s side since I was only concerned about 6 & 8. It was between 420 and 422 psi on all four, so no bent valves or holed out pistons. I was going to compression test the passenger side just for completeness, but after trying to wrestle my glow plug compression adapter and hose into #7, I said the heck with it.

This weekend I picked up two Ford reman’s from the dealer and installed them. One thing of note, everything I have read on installing injectors has said that when you reinstall the plug into the rocker box, make sure to orient it with the bar code facing out. I did that, and put everything back together thinking, wow I am almost done. Not so! I couldn’t get the injector harness to go onto the injector plugs. Long story short, the indexing notches were not oriented consistently with the bar code. I tore it down again and reoriented the plugs so the notch direction matched the others and reinstalled everything for the second time.

Before starting I did an injector buzz test to make sure the harness was connected correctly after my previous revelation. I added some soy shield to the filter housing, crossed my fingers and cranked. On the third try it fired. It took a minute or so to burn off the fuel left in the exhaust, but eventually it stopped smoking and settled into a nice smooth idle.

So, no Cummins conversion for me this time around.

Thanks for the comments Harry, I have had a regulated fuel return with pressure set to 65psi for ~100k miles. I also have an AirDog as well as a fuel pressure gauge in the cab. During the whole time, my fuel pressure was rock solid.
 
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Curmudgeon
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472 Posts
Glad to hear things went well.

And thank God there won't be an Excursion parked on the side of the road clogging up Tinton Falls traffic and killing mosquitoes.
 

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Senior Member
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3,051 Posts
Were fortunate to have a few nice bore scope cameras that fit through the injector nozzle hole of the cylinder head and down into the cylinder to take a look at things if there is any questionable circumstances. But sounds like you caught everything in time. I assume you torqued the injector hold down to spec, early like yours is 24 ft lbs and later with wavy oil rail is 28 ft lbs, and sorry you had to remove the valve covers again for the connectors, for future if needed, it's better to plug them together before putting valve covers back on.

Glad you up and running again mpropst!

Harry
 

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Junior Member
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28 Posts
Discussion Starter #11
My borescope works well on gassers, but was to large to fit through the injector nozzle hole. It did give me a nice view of the injector bores so I didn't have to brake my back physically looking down there to make sure they were clean and clear. I did torque them to 24 lbs. I was going to connect them before putting everything back together, but I was paranoid of dropping a clip. I didn't think to just plug them in and clip them later... live and learn. I assume I am good to go considering compression was good and equal and she is running smoothly.


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