I'm betting on a bad injector in this case as well. I know several have replace all 8 of there injectors and noticed huge improvements with power and economy, as well as a large reduction in noise. You could probably talk to the vendor and let them know your situation. That way you have some time to swap injectors around if indeed it isn't #3. But if you haven't done the intank mods and pre pump mods yet, I would suggest doing them anyway, as it is pretty substantial the amount of noise reduction. I could actually tell a reduction with out having to listen for it.

It will sound like that. Try this, get rid of the one quick-connect at the suction side of the oem fuel pump, go top off with fuel, drive around, stop, get out and put you ear to the passenger wheel well. If the "knock" is gone, it's cackle. Then, and it's a big then, start researching fuel system mods. Your head will be spinning. But that's ok, cause you can ask everyone on here what you're confused about and you'll get the answers you need. Oh ya, get out of the stealership 1st. It may be a bad injector, but try what is suggested here, and I'd bet a cold one you save some money, maybe even do a repair and feel a lot better than you would being jacked by the Stealer.

Here's where I bought a replacement. http://www.xtremediesel.com/index.as...ROD&ProdID=206 . They say to call for best price, I bought one just a while back, $190 + $150 core. They are brand new OEM Alliant injectors. Good luck!

Fuel knock is not an overly fueled engine on the verge of hydro locking. Fuel knock is when non atomized fuel is burned/explodes, due to poor atomization (problem in the fuel system, bad injector tip, poor fuel quality, or lack of air for complete combustion. You can totally break a tip off an injector and the engine will run and rev up. You will be pooring fuel out the exhaust and smoking up a storm and a half. Overfueling will give you black smoke. Look at an old mack pulling a load. Cackle is inherent with navistars design of the fuel system and should not be confused with fuel knock (stated this in my other post).


If ford diagnosed #3 then buy an injector and replace #3. You can check there diagnosis with a heat crayon. Mark the manifold and see wich cylinder takes the longest to melt and or melts extremly fast. A raytek gun works the best for these situations though.

I agree, I'd replace #3 and see where that gets you. I'd advise you to get it doon sooner rather than later as well. If the #3 injector is that bad, it could wash you #3 rings out pretty fast, and then you will need an overhaul.

I hear ya and i hope that hasnt happend allready. I also have more black smoke now, even noticable with the edge products. But thanks agin for all whos helping me i will post with results. later Chase

Hang in there Chase, somebody here recently had your exact symptoms. It may have been Cangim, and maybe not but I believe he changed an injector and a few other items on his quest. Maybe they will chime in soon. I do specifically remember the hammering symtom though. Hopefully they will be along soon.

Edit: Duh, read the whole post. I think it was Hink. Talk to him.

hey thanks again for all who is helping me. I just ordered a new injector for my number 3 cylinder, I will post with the results, hope it fixes the prob. Chase