Red= Inside Connector
Blue= Outside Connector

 

Ohhhh, the connector!... Thanks!

Josh

 

Ok guys here it goes....... So after driving for around 5000 miles i started to have the same problem. Slow to start then hot no start. The other day i took the passanger side valve cover off because i discovered a leak on that side. Replaced all four injector top seals, put it back together and drove it for a week. Was starting fine, and then just a few days ago same problem, hot no start. Last night i again replaced two injector seals on the passenger side, that i had just replaced.

This morning side hot not start.

Has anyone seen bad injectors not bleeding off cause this problem???

Also i have not had the drivers side off again, but i dont hear any leaks from that side. Its hard to tell with that baffle on though.

One last note. I also replaced the dummy plug just in case with a new one i had in my garage.

 

Excellent write up Thank You Very Much.

I just finished all injectors but did not do the nipple cups and seals. Its in my list as soon as I get the tool.

My only question, the retaining clip that holds the injector top seal in. The clips in my injectors are a bit different then the ones in the Alliant Kit. they don't have the end to get a pick under to help with removal. I screwed around with them for a while and finally just changed the seals without removing the clip.

 

Ok guys i checked the IPR with a known good one and same results.

Id be suprised if it was the pump. This is on a 2006. Any way to tell for sure if its the pump?

 

Yeah the OEM clips can be a real PITA to get out. It takes some practice.
I'm impressed that you managed to replace them without taking the clip out.
Do you mean that you pulled the old one out then used the extra space to then get the old clip out and put the new seal in, or did you force the new seal down in there with the clip in place also?

 

There's a Couple YouTube videos showing that technique.

Josh

 

Yes, Pull out the ICP and crank with the ignition wire with a big rag over the hole. If you get a lot of oil coming out your pump is good. You could also use a very high pressure gauge in the port.

Find a shop with a nitrogen tank that will let you hook it up to your truck. The 1000PSI will make any leaks very obvious.

Looking back at your last post with the summary of what all you've done:

~Standpipes
~Dummy Plugs
~IPR
~Injector Top Seals
~STC fitting


Are all of the nipple cup seals replaced?
Are the nipple cups themselves in good shape with no scratches or gouges in them

I thought I remembered you had replaced the STC and all of the Nipple cup seals, but I must not have read back far enough.

I Suppose It may be possible that maybe the spool valve/piston is going bad and the internals of the injector are leaking pressure, but I would think that would also show up as a bad injector with a power balance test or throw DTCs.

 

I have not done a power balance test. I am going to get a copy of autoenginuity this week to do power balance test.

Yes, i replaced everything.

Here is exactly what happened. So i did a air test, replaced the injector seals that sounded like they where leaking. Kind of hard to tell. Then replaced the nipple orings. At this point though it was still leaking air from the empty rail. I added a little oil to make sure all the new seals had a nice coating of oil to the rail, then repeated air test and no air was leaking out anymore.

Im sure when i get home and do a air test hot, it will sound like air is rushing out of the passenger side valve cover. When i take the valve cover off, it sounds like the air is coming injectors, but i can never pinpoint the air leak, with my hand or see air rushing out.

 

If it's bad enough to get a no start, you should see a pretty obvious leak somewhere. Anything that brings your ICP down below 300 is generally pretty easy to see and feel, especially if it's at one of the injectors.

Are you closing the IPR with 12V?
Auto Enginuity allows you to command it closed.
If you don't have your IPR closed you will always hear a leak.

What is your ICP cranking?

Are you monitoring everything else as well?:
FICM voltage
Fuel Pressure
etc?

 

Ok so yes, I actually have a bulletproof diesel 58volt 6 phase FICM. Brand new NAPA 875 cca batteries. Always peg the FICM voltage at 54.5. Highest it can read.

I do close the ipr with 12v.

Cranking after over 150 degrees the icp is never above 250. Pegged at 84.5

Cold it takes about 10 seconds to get over 500 to start pegged at 84.5

I mean when I do the air test I can hear it and it sounded like the injectors so I changed the seals and it still leaked so I moved to the nipple cup orings. Put it together again, still sounded like it was leaking some. Dropped oil into the rail, re tested and the leak went away. Accept the very very faint leak. In the area of hpop.

Started it up and drove it last night. Got it to 150 degrees and hot not start with the above results. If it stays running its fine. A little high ipr values, but runs ok.

I have not taken the drivers side off yet but I cannot hear anything from the baffle with a large funnel inside it. So I don't think it's there.

I wonder if autoenginuety will show an almost dead injector?

I even swapped out a new dummy plug on the passenger side. The stand pipe looked totally fine and the orings looked good.

 

One other thing of note, I have a sct livewire with innovative diesel extreme street tune running ,and I've never seen over 2200 psi at wide open throttle. At WOT I seen 94% on ipr.

Not sure if innovative messes with the scale or not. That 2200 seem super low to me.

Cruising at 70 mph flat ground the ipr is around 36-41 %

 

With AE you can monitor ICP desired and any difference between desired and actual points to a leak. You can also WOT up the steepest hill you can find. If you have a leak it will go to 84% and stay there.

I'm kind of leaning toward a bad HPOP/STC yellow O-ring. If that's all the ICP you're seeing you have a big leak somewhere and since it's not apparent with the valve covers off, it would probably be back under the HPOP cover. I don't think a cracked branch tube would allow you to start cold.

 

I kind of am leaning towards the pump too. It's just rare on 2006 trucks. Branch tube was tested last time I had it apart.

I can get my hands on nitrogen at work. Maybe I'll order a tank.

I don't understand the 2200psi thing at WOT though. I wonder if innovative changes the psi scale to trick the injectors into getting higher psi.

The thing that's strange is when I put all back together, I lube all o rings and seals. Plus when I pressure test the leaks after that I can still hear leaks. When I dump a little oil in the icp hole then pressure check again the leaks go completely away. I that normal?

 

Ok, so today I did another leak test. Sounded like the passenger side was leaking again. I have a video of it.

I took the oil rail off. Put two dummy plugs in it to seal it and covered the injector cups. Applied air to it and I had zero leaks.

I then pulled each injector and put them on the rail. Each had a very small leak. I'm hoping this is normal. I will try to attach video when I get home.

My question is this, will I hear a very slight leak from the injectors venting? Or is this not normal?