How can you tell if your injector is going? I understand about fuel in the oil, white smoke on startup, loss of power etc. What sound might it make? I have a knocking/ticking/rattling type sound coming from the middle front of the engine, but I can't figure it out. The engine was rebuilt 10,000 miles ago and the #1 injector was replaced as well as the engine being bored .40 over. The sound is intermitent, but when it occurs it is in rythym to the engine. When I lean over the engine it is not as prevalent, but it seems the loudest hanging over the fan shroud in the middle front. What sound would a pulley make if it was going?? This sound is going to drive me crazy until I get it fixed! Thanks!

 

You can run injector performance test. That will show if all injectors are working at 100%. Does fuel pressure fluctuate more then 500 psi? If it does you could have FCA going out. Injector kill test can also isolate the noisy injector at idle. Fastest way is using a Starscan to perform test if you know someone that works at a Dealership or pay to have test done. Usually injectors will run 98% or higher during test if below 90% you could have a problem with that injector with low reading.

 

first check the isolators on the injector lines. it is a blue colored clamp. if it is loose it will cause this and will cause the line to fail and especially the #4 line on the 06. next check the valve lash the exhaust on the 06 is more than the earler engines when i changed my cam i set it to 0.010 on the intake and 0.020 on the exhaust then i seen on a forum it had changed and i had to go back and reset. the bad part was it is stamped on the plate that you look at while working on the engine.

 

Some/most who have had that 'mystery' sound like you are describing HAVE had to replace the FCA. If you do not have white smoke, the FCA is probably it, and it does seem to be a 2006 'thing' for whatever reason.

I had the 'mystery' sound and found it to be the injector line isolators/blue clamps. Once I tightened them, the sound went away. Many have actually found that it is the bottom mounting bracket bolt that screws into the intake plate that is loose rather than the clamp at the line itself. So you might want to check them before going deeper in your search of your noise. My isolator clamps were tight on the lines, but I did have a couple loose mounting bolts at the intake plate, and the #4 was very loose as compared to the others. I used a small dab of blue locktite on those bolts, they are still tight 30K later after tightening them.

If your clamps are not loose, then go the direction that BigIron70 suggests. Better to test and see what you have before getting into other things like valve adjustments. You may end up at valve adjustment but you will have ruled out stuff with the right testing in advance. Look at the bright side, you will know via the testing what is good first. Plus, you just went through your engine, you would have done valve adjustment 10K ago after your overbore, so your valve adjustments are probably OK if you used the specs that you see on the valve cover.


CD

 

Thanks, I checked the fuel line brackets before and the #4 was a little loose, but I checked everything by hand, so I think a full blown "wrench" check is in order. Next I think is the valve adjustment as there is a ticking when driving. I didn't do the rebuild myself or know the shop that did, so I not trusting anything.

 

My 04.5 does the same thing if in "Park". When in gear it stops!!!

 

Do I dare ask why you rebuilt the 06 mega? Please tell me it had a zillion miles on her...

 

I guess it depends on why the injector is 'going'. On mine, about 105k miles ago, the truck sounded (and felt) like a 6 cyl running on 5. Oh, cause it was. Doesn't sound like your issue though.Mine was intermittent also. Began about 1/2 way to Los Angeles and was mostly running on 6, but intermittently would go to 5. I made it back home and to the dealer for a new #1 stick.
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