2003 Honda civic 1.6 flashing cel, lumpy idle.
Replaced the engine after a major cambelt failure, misfire and flashing cel, replaced so far:
Cambelt
Tensioner
water pump
Crank sensor
Cam sensor
Head gasket
4 coil packs
4 spark plugs
4 injectors
common rail
air intake temp sensor
knock sensor
vtec oil pressure sensor & solenoid, complete housing

Checked,
leak down test all green
chemical coolant gas test, no exhaust gas present
Timing checked a dozen times
injector signal present,
no air leaks,
valves all good and set correctly

Currently I can sit and rev the nuts off it but as soon as I try to drive it away, it sounds rough and cel starts flashing.

I am now at my wits end and considering writing it off.

Codes, sometimes misfire on cylinder 2, sometimes cylinder 4, or any random misfire.

 

After 2 months and throwing £600 at it I'm phoning the customer to say, come and collect it, no charge, I give up!