So I just got my car back together and it is starting to me a very unconstant rock pebble noise sounds like little rock or something is bouncing around in the motor. the noise only starts to happen after the car is fully warm

First the car starts to idle surge and then make the noise.

At first we thought it was the head but we had a shop check out the head and everything was fine.

The weird part is if we hold the throttle at basically anything higher then idle the noise goes away.

My last guess is it has to something with the oil like the motor is getting enough and im having metal on metal contact some where making the noise.

my oil pressure is reading around 25-35 at idle. so there is pressure there


if anyone has run into this problem or thinks they know whats going on please help!!!

 

Someone has to have a answer haha I cant be the first with this problem

 

check valve adjustment i was recommended to run .007 on both intake and exhaust. after that if noise still continues it might be worn out lost motion assembly. this is all assuming that you have stock internals,and are not running after market pistons. if so i could also be piston slap. at idle oil pressure should be a minimum of 10psi anything more is good.

 

We dropped the oil pan and the bearings look good

The LMA are brand new

After market pistons and rods

but after holding throttle little higher then idle would there still be piston slap and louder

 

Im having the same issue. Was totally confused. Took it to a local shop that is known for building hondas and he thinks it might be piston slap from cylinder 1. Might have been honed too large. I'll know for sure once he gets back to me.

 

did it start to idle surge?

and if u held the rpms higher did the noise continue?

 

Your idle surge is probably a tune issue and is unrelated, but yes it got louder as it climbed towards full temp. I believe if i revved it the noise went away, yes

 

See my noise doesn't come on till its at full temp and neither does the idle surge the problem has to connected, we checked for piston slap and cant see it being piston slap cause there would of been marks.

 

Someone help this guy out....

 

Can a Bad oil pump make a car idle surge?

 

the idle surging could be your iac duty cycle check with your tuner on that if you have s300 it is fully adjustable, for changes in weather and such. while you had the oil pan off did you happen to try and look at the cylinder walls? and i would check with who ever built you engine to see what piston to wall gap is. to much ptw= load *** pistons.

 

I just told you that the noise got louder as the engine warmed up. As far as piston slap goes, there doesnt need to be scoring on the walls for it to slap. You will have to remove the piston and mic it. Then do the same with a dial bore gage on the cylinder wall. Stop worrying about the idle surge its a tune issue guaranteed.