I have a 2002 Honda Accord SE with the 2.3 L4 SOHC with the engine cast of F23A1. Its done gone through 3 DIFFERENT heads.

I had replaced my valve cover gasket amd spark plug tube seals, where i uncovered that all but 4 roller rockers had excessive play in them. So i was heading to the dealership to return it because i know it was a bad thing. But it JUMPED TIMING on the way up there.

The shop had my head machined and REBUILT the top end of the engine with a new camshaft, valves, springs, roller rocker assembly, cam gear. It lost power on the test drive the mechanic insisted on doing for me. It spun the KEYWAY on the cam gear.

Then we put a NEW head on it, and replaced the water pump and timing tensioners, timing belt, new drive belts, distributor, changed the oil, flushed the coolant. It drove for 52.6 miles and started TAPPING, so i killed it and had them come and get it. Not sure what happened this time.


Code read the computer and these are what it was throwing
Car Scanner ELM OBD2
DTC report
Selected brand: Honda

============1==============
P0325
Raw code: 0325
ECU: 0E
Status: Confirmed
OBDII: Knock sensor (KS) 1, bank 1 - circuit malfunction
Honda: Knock Sensor Circuit Malfunction

============2==============
P1259
Raw code: 1259
ECU: 0E
Status: Confirmed
OBDII: Immobilizer to PCM Signal Error
Honda: VTEC System Malfunction; VTEC System Circuit Fault (Bank 1)

The VTEC code was there ALL 3 times it died, we used a KNOWN GOOD VTEC solenoid.

Timing was fluctuating between 30° and -10° based on acceleration and deceleration.

On start up and idle it was steady at 12°


I have also attached graphs of my timing advance through out the time period it was running with the 3rd head.

 

Just saw this thread.

EDIT: I'm not sure what is happening with your engine. What did the shop determine on the most recent return of your Accord?

 

I havent heard from them yet. I think it dropped the valves