Sorry if this topic has been beaten to death.
Besides measuring the ohms on the injectors is there any signals or sign that they are going bad? What happens when one or more are bad?
And can they simply be 'leaking' inside? Is there o-rings that can be replaced rather than replacing the actual injectors?

I'm getting real bad sputtering/rough running with no visible signs of fuel leaks. I just replaced all fuel lines (with exception of HP lines coming from IP) with rubber. I see now visible signs of leaking around the injector fittings where the lines go in.

The VP44 is new as well as lift pump.

??

 

you cant measure the ohms of your injectors as they are not electronic, really the only way is to pull them and have them pop tested at a diesel shop, or you can order replacement sets from ebay for decent prices

 

i am pretty sure if you have a later model 24 valve with the bosch injector with the soloniod on top, then yes you can check the resistance(ohms) remove both wires from the top of the injector then make sure it reads less than 1 ohms any more and you have trouble. I have also come across injector lines leaking through not bieng torqued corectly and even coming slightly loose over time so check those as well.
without seeing or hearing or even knowing the year and model its hard to give any real diagnosis. Again if its the newer 24valve HO engine then yes 04 and up yes they can & do have problomatic injectors.

 

The injectors were not electronic until '03.

If it's a VP44 truck, there are no electornics to measure....the injectors are jerk style. Like dodgetrucker75 said, the test for them is to get them pop tested and make sure they're all opening at the correct pressure.


You said you just replaced the lines and now you see leaking at the connector tubes.....there's your problem.

 

Thanks Paul,
No, its an '01 HO .
And yes, the 'nut's have been OVER torqued about 12 times. I am THINKING its in there someplace. SOmeone told me I may not necessarily SEE any fluid coming out of there. I had problems with air in the lines and between 3 half-assed mechanics they have taken those lines off way too many times according to many. If not visually leaking, then what would be going on? Leaking WHERE? Where would that fuel be going?
IF it was this, is it 'safe' to get a used set of all 6 lines if used only 1X. ?

thanks again.
oh, and heres another little thing that goes along with this. IF the truck has diesel fuel in it, the sputtering is a lot worse and it won't start (fire) when warmed up (and barely when cold) unless you unplug the lift pump. If even 20% bio diesel or WVO is added the truck starts every time and sputtering is a little better. I'm thinking its definitley getting air in it someplace?
At one time (when the popping was not as bad), I did see fuel leaking from the injection line nuts leading into the injectors. After that they were tightened beyond belief. lol

Once again, the IP is new and so is the lift pump(s) ( I have 2 installed).

 

Like coaltrain said we think your problem is in those lines and if you over torque them then they will stretch and to me are now a throw away item. a set of lines will be a lot cheaper than a set of injectors. I cant remember what my fuel lines where torqued to but i did it anyway on all 3 of the trucks that i had to do injectors on.
you may not see the diesel leak but a raw diesel leak like that you should be able to smell it. I woul like coaltrain suggests change those lines first.

 

Ooo, BIG typo.
That was supposed to read " I see NO visible signs of leaking" which is true. I see no leaks but the popping is worse than before.
I'll look to change out those High Pressure lines. I just assumed unless I could SEE a leak that I didn't have one (externally).

However, the high pressure lines at the connector to the Injectors WAS leaking and I think they got WAY over-torqued.
Does this make sense? If they were over torqued and taken on and off God knows how many times, it could be leaking where I can't see it?

Thanks a lot guys. I'll look for those lines and see where that leaves me. Hoping not to have to take the injectors out.

 

Well, the next thing I would check is the connector tube nuts.

If those nuts are not torqued down to AT LEAST 38 ft/lbs, the tips of the tubes will not fully seat against the injector body and the fuel goes into the bypass circuit.

There is a bore in the head that is a return passage and if the tube isn't tight enough (or is so tight that it distorts the connector tube), the fuel goes through this circuit and returns to the tank.

This is THE most common thing I see guys screw up when putting injectors in. I'm not innocent of it either.

It makes the truck hard to start, it'll lack power, you'll get smoke, and the truck may sputter and die.