Cat injectors

What serial prefix is this engine, and at any time has it been plugged in to rerate by a cat shop?

Injectors just don't stop working part of the time, and worn out injectors actually tend to smoke more.

How did they check the pressure?

I hate to say it but your likely going to throw money at something that isn't going to fix your problem, only mask it.

 

I think it is a 6nz. He mentioned this prefix in his first post so I assume it's this one. I wonder if it was plugged in they could have given the low nox file?

 

It's possible, but I think there is something with the fuel system being missed and not the injectors, new transfer pump could even be not working well.

I would be going thru every fuel line and swapping filters before dropping $3500 on reman injectors that may not fix the issue, but that is just me.

 

Did they replace the fuel check valve? I'm with smoking cat. The injectors just don't quit working like that. Now with an e-model the injectors don't work like an old b -model. The e-models injectors actually will fuel less with age. Where a b-model will run better.Do you have a restriction gauge for the fuel? Is it well above 5? If so you may have a fuel line that has swelled up from age restrictions fuel flow.

 

If they had the front structure off to fix oil leaks and did all that work and then the problem occurred...I would lean towards they didn't time the cam gear like it should be. I know you said they have checked the timing but if they got it a tooth off it will affect the power. Like the others have said. You will just be throwing money at it as far as replacing the injectors in hopes of the power coming back. There is some other issue other than injectors.

 

if a 6nz is off one tooth it wiil get a cel light

 

I believe engines after the year of 99 will already have the low nox file. It is a file cat installed into the ecm for emissions. Low nox is a programing they do with the ECM that reduces nox.

In the older engines they had a file called pre low nox file, which is the better one. What happens is people take their truck into CAT for a rebuild or engine work then they'll reflash the ecm to the current low nox file. The owner then complains of lower power and bad mileage.

I don't think this is your issue, but a fuel delivery problem.