knocking/banging from upper motor

[tuner101]

hi guys,

me and my brother have a SHWEEET 92 gs eclipse w/ turbo. thing was beat to crap, 190 k the kids before me had the boost at 20 psi. i dunno how that worked out, i was under the impression it would go into fuel cut...but i dunno. ok on to the problem.

i get it started, there is a Very loud very distinc banging coming from the upper engine give or take. it sounds like its coming from the valve cover, where the cams are, or where the crank/camshaft position sensor is. we took the valve cover off, and one of the cam lobes had a little nick in it, one of the lobes on the intake cam. we turned it over with the valve cover off and that lobe doesnt hit anything and when you turn it over, not start it jsut turn it over there is no sound. also once i get it running and rev it up a little, like .5k-2k it gets worse, sounds like something is broke in the head or somethin and is knocking around, then at 3k it is signifigantly better, but still there intermittantly.

any ideas? thanks in advance

Nate

 

[TRBOBLU]

Sounds like a rod knock. When my rod bearing went I had very similar symptoms. It would knock very loud up to about 2.5k and then seem to go away. At first I thought it was coming from the head(sounded like a rocker arm getting banged around in the valve cover), but I bought a stethescope(sp?) got under the car when it was running and listened to the oil pan. Found out it was the #2 rod. You can also pull 1 spark plug wire at a time while the car is running and see if the noise goes away. A wrist pin or rod knocking will go away when the cylinder is not firing. Hope that helps.

 

[tuner101]

ya , that helps a lot, i was thinking it could be knock, the car is old and mabe one of the injectors is crapping out, i got the possibility of a spun bearing or a collapsed lifter as well, the motor is old, and im going to get a short block next summer, so i dont wanna destroy anything obviously, but ill try the stethescope idea and check for the spun bearing. thanks

 

[Froyd79]

Does this motor have a balance shaft eliminator kit? Is there alot of oil pressure to the head? Might be the cams w/ no lubricant grinding into the casting.