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LOUD KNOCKING injectors didn't change anything

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6.9K views 16 replies 8 participants last post by  dsldude  
#1 ·
Ok sorry for the long post want every to know the details. About a year ago my truck started blowing white/blue smoke nothing major after the first cold start of the day that's it and not for very long 30sec maybe and this spring I took the truck to a car wash. I started the truck to go home and wax and I noticed this small knocking almost more of a tic, didn't think much of it pulled it in garage to wax it. Got done and started it to pull it out of garage and a horrible knock developed i mean I can't drive the truck it starts but not drivable i moved it to the driveway and parked it. It has no power and now makes white smoke while running doesn't pour it out but still bad. Kind of assumed it was injectors since I just got a nice transmission and put a big tune on it and had a lot of rp on tune so I didn't test them as soon as I had 4K to put into injectors I did. anyway I just got 100hp from II and dropped them in took my time doing it i did it to forum spec also a few vids from YouTube. no noticble problem doing the swap did a valve lash before starting it back up and today when I started it same dam problem loud knock white smoke. I guess maybe I could have installed them wrong I'm going to go through it again to make sure no leaks and torque specs are good but idk where to go from here. Thoughts???
 
#3 ·
Injectors from industrial could very well like said above be bad out of the box but I would also do a compression test.
 
#4 ·
Truck has very little blow by small haze nothing out of ordinary. and yea hoping test tools are cheap doing it in my driveway to keep the bill as low as possible and they are remans? But what are the odds of getting a bad injector. I emailed ii hopefully they give me good news they have been great so far and Yea I'm really hoping it's not a major problem.... guess I'll start trying to redo my work double check and if still knocking I will compression test
 
#6 ·
Yea already spent 3400 on these injectors can't imagine I got sent bad ones. II said it's possible but they test them before they send them so he said look at other issues but today I'm gunna retorque everything and double check my work then if it still knocks I'm gunna drain oil and rip open oil filter hopefully no shaving but on dipstick there isn't anything wrong no shavings no discolor it's a little overfill from my last injector I'm pretty sure but after I change my oil I'll know for sure. Ii also mentioned to test rail pressure, thought these trucks needed to make ridiculous psi just to start? So idk does he mean maybe a bad cp3?
 
#7 ·
Stop guessing- start testing. 100HP injectors are likely to haze, made worse without tuning for them. If you feel like its an injector knock buy a rail cap and cap one at a time until the knock stops. Now bare in mind stopping the combustion can eliminate the sound of a rod knock. If you find the hole thats knocking send that injector for testing. If it tests good you may have a rod knocking. But I can tell you from experience an injector knock can sound like its about to throw a rod.
 
#10 ·
No doubt injectors can and will cause noises that sound like a rod knock. The problem I see is the noise was there before these injectors were installed and it is amplified because of the amount of fuel with these new injectors. I have seen several wrist pins cause this noise. Not saying this is your problem but cap each injector until noise goes away and then you will know which hole has the problem. If you find the noise switch that injector to another cylinder and see if the noise follows. If it does it's a injector problem if it doesn't move then it's in the hole. Good luck
 
#11 ·
Rail pressure sensor? Mine did this when mine was going out. It didn't throw any codes right away, but your symptoms sound similar. I bought one off ebay (new bosch) for 70.00 and bingo. No more knock, no more smoke. I dont know the quality of the part but it works great! Worth a shot.
 
#17 ·
Futile meaning pointless. It would not help you figure anything out is all.