I have an issue I've been battling the last few days. Car starts/runs/idles fine up until 170-185* range. Without any notice the car will begin to knock and sound like there is a mechanical issue. It is never consistent. Sometimes I can let the car idle for 30+ minutes and with a quick rev the noise will come back and then go away when a load is applied (backing it into the garage) and then a quick brap of the throttle again the noise will come back. I set the valves and put the plug wires back in and started it to see if I could visually see anything in the head at idle that could be causing the issue. All looked good. The car had Brad Penn 15w-40 in it when the noise started. I changed the oil and filter and put Mobile 1 15-50. It seems to have helped a little. The original filter did have some aluminum shavings in it but I don't know how long it has been since that was changed or any prior history on the oil/filter. I started the car and verified I had good oil pressure with a mechanical gauge. Ran it for a good 30 minutes at idle with the tick/knock going on and then drove it around the block a few times. Killed it, and cut the filter. Filter was spotless. I'm at a loss of what could be going on. Anyone have any advise? Car is a sleeved b16 with a portflow built head.

 

Sounds to me like you might have a bent valve, that would explain the ticking sound you are describing. And the metal shavings are definitely not a good sign you need to keep checking your oil an wipe some off the stick with your finger an look for any metal shavings. If you still have them that would most likely be your rod baring. Hope that helps.

 

I've been driving around the car. I've cut two filters since the dirty one and they were both spotless. I believe that the rocker arms when heat soaked are contacting the edge of the titanium retainer ever so slightly. I wanted to get some miles on the car so that I could really examine the casting lines in the rockers. I will update this post after I figure out what is going on. I can't be the only one to ever have this issue.

 

Have you popped the valve cover off and taken a peek yet?

 

I've looked at the following things

Engine oil pressure with a mechanical gauge
Filter cleanliness
Cams
LMA's
Head bolt torque
Cam Cap Torque
Valve springs (compressed with a soft blow hammer by hand to see if any felt weaker)
Retainers for contact
All keepers in tact
Rocker arm pad and foot condition
Valve Lash
Mechanical timing
Distributor drive

Noise doesn't change if injectors/plug wires are pulled. I've disabled the vtec solenoid and it didn't change it. Noise doesn't get louder with the oil cap removed.

 

Is it fast or slow. That could guide you in the direction to look. ie. crank or cams

 

I have video. I'll post it up tonight when I get home