jsg1113

I have a 2003 LQ4 out of a van that I'm putting in my offroad truck. It fired right up yesterday but had a loud knocking noise. The noise changes consistently with rpms. Sound is loud like a rod knocking but I pulled the pan and rod bearings look ok. I did unplug each coil one at a time and the knocking quit when #5 was pulled. If the rod bearings are good are there any other suggestions? Lifter? Rocker? Any help would be greatly appreciated.

slogo

Im no expert but my neighbor had a loud knocking sound also, his turned out to be
the part of the piston over the top ring had broken off, maybe an inch long piece.
his was also a 6.0 out of a van bottom end was stock. hope thats not your issue.
good luck

Taxman20

iTrader: (11)

If it stopped when you pulled the plug wire, then its most likely in the piston, wrist pin or rod bearing. Since you didn't have spark, there was no pressure on the piston so it was just free spinning.

CattleAc

iTrader: (7)

Sounds like you've almost got it apart, but hopefully you'll luck out.


Last one I rolled the dice on, and bought with a "knock"...turned out to be this...


This sounded so much like a rod, the guy almost gave it away.

jsg1113

Wow that looks bad!


Thanks guys for the replies and help. After a lot of troubleshooting and very little progress I am going to pull the motor and swap for a different one. The place I got it from is going to give me another motor.


Thanks again for the help!

dniemi

I also had the flexplate crack and was sure while I was driving that it was a rod bearing. I got lucky and it was only the flexplate but was cracked 90% around.