Need Injectors or a nasty air leak??

[4x4TruckinGirl]

I have an injector problem (i think). On morning starts at any temperature, the truck fires right up then the truck stalls out as if it ran out of fuel. To try and get it started again, I have to crank it for quite a bit, and upon starting have to rev the engine a bit till it catches and goes on a high idle.

Throughout the day it usually starts up fine, unless its sat for a few hours, in which case it sounds pretty rough on startup. The truck surges sometimes while im driving. Some black smoke when the motor is put under a load. White smoke on startups 1st thing in the morning. Also, my fuel is going places a lot faster than I use it. Around 2 injectors it seems damp with fuel on the top.

I have already replaced the lift pump, and fixed a few air leaks in the fuel system and replaeced some fuel lines.

 

[Exekiel69]

It looks like it could be the return lines or some O rings. I would start following te fuel lines from the ful filter to the tanks. Is the fuel filter new/old? is it tight?

 

[4x4TruckinGirl]

the fuel filter is recently replaced and is on tight...

and i have no clue how old these injectors or IP are, guy that had it before me didnt share much info on the truck.....

 

[93turbo_animal]

sounds like an air leak not injectors and if a couple are wet around the top it sounds like you need a return line oring kit

 

[sle2115]

Sounds like air to me as well and if the injectors are wet on top, you prolly need the return "t" kit.

 

[oregon dw]

It sure sounds like air is getting into the fuel via the return lines and o rings. I'd suggest getting a return fuel kit and replace all the return lines, clamps and o rings that run from each injector. A lot of us 6.9's have had air getting into the system via the o rings. Replace as a whole set, at the same time.

Also make sure the fuel filter is tight. Any fuel that can leak out will leave air enter at any joint. Air will go in before the fuel leak is seen, and they are the hardest to find.

Another "mod" is to block off the return line at the fuel filter, and only there.
I took it off the 90 degree elbow and plugged it with a 1/4" bolt. A short couple of inch 1/4 " fuel line also plugged is attached to the elbow at the filter. On my 85 6.9 it's the right bank return, the left bank remains hooked up to the IP.(that has to be left as is)

Start with that and see if it helps...good luck.

 

[sle2115]

Another "mod" is to block off the return line at the fuel filter, and only there.

Or, instead of blocking it, use a piece of clear tubing where it returns from the t's to the fuel filter head and look for sign of air. Oh, and you can get the kit here

 

[Agnem]

First I've heard of anybody blocking off the return line at the filter. That's the fuel systems last chance to avoid sending air to the injection pump.

Anyway, I see from your sig that this truck is a recent aquisition. If you have not read the Fuel System Servicing article (link in sig below) in our tech articles section, you might want to, and at the very least do a complete R&R of your return lines, T's and O-rings. Definitely the cause of your problem. Welcome to the site. Good to have another lady here. You'll make friends with Tanya pretty quick I suspect.

 

[4x4TruckinGirl]

Alrighty.... I'm on a mission then... off to get the kit with o-rings n tees and return line.... Thanks for everyones help! much appreciated.

 

[Darrin Tosh]

Nice Lookin Truck!

Welcome to OB!,

 

[Mr_Roboto]

Good to see you made it.

Sweet looking ride!

 

[93turbo_animal]

I didn't do it Mel and I don't know why it was done but the return line is blocked off at the filter head

 

[Diesel JD]

Welcome aboard. I have replaced that fuel elbow with one that has no fitting for a return line and blocked off the return from #1 injector. Dieselmann advises this modification if you have a truck that just wants to suck air. The other place I would suspect for air right off the bat is the stock fuel/water sep, assuming it has not been bypassed. Its easy to bypass, but if you do, you really should get an aftermarket unit. I have one I will let you have cheap if you want to do that. The basic problem is finding replacement filter/sep. elements for it. I change mine so often with the biodiesel stuff, and my fuel goes througha water sep before it ever goes in my tank, so I feel pretty safe with it no sep. on the truck. I have no problem sending air to the IP, but if I run it out or get a bad filter, then I have a devil of a time bleeding out the air. You should start by having your injectors tested at a shop and putting on a new fuel return kit and replacing any bad injectors, or teh whole set if you have 2 or more bad ones. Don't let a shop charge you more than a few bucks to test the whole set. Tell them forget it and find a decent shop. Have them check for spray pattern and pop off pressures. Good luck, write back if you ahev any more questions.

 

[spencnaz]

I'm having the same issues, but I've replaced the return o-rings, injectors, IP (it was really bad along with the injectors). The water separator has been bypassed as well.

I fixed a loose fuel connection on the fuel tank and I'm still getting the symptoms she described when I first light off the PowerSmoke in the morning. Once it's warmed up it will light every time.

 

[DFH]

You could also just install an inline electric fuel pump if you think that you have air in front of the injector pump to get a good prime. It is a good thing to install regardless.