Chetan,
I would like to add C.R as well for relation between Ignition Retard/Advance & AFR. Let me try to explain that but before that i would like to state few terms which will help you understand the relation between all these, now most of us are aware of four stroke cyle so i will not explain that, we will be concentrating more on the power stroke of an engine, The power stroke can be thought of as an avearge (theoretical) pressure which is result of combustion of air/fuel mixture in a combustion chamber which excerts pressure on piston to rotate the crank, This theoretical average is called mean effective pressure M.E.P
take for eg 2 identical engines in terms of cc valves a/f ratio etc but one engine has C.R of 9.1 & other engine has 11.1 ,
The engine with 9.1 C.R will have far less M.E.P than an 11.1 C.R engine because C.R controls the heat in chamber before its ignited,lower c.r will have low burn rate the temperature rises depending how much fuel is compressed, thats why lower C.R needs more timing advance because it takes more time to burn/heat & raise pressure in chamber, therefore to time peak cylinder pressure for a slower burn rate & slow pressure riser requires more advanced ignition timing. where as for a high C.R engine less advanced ignition timing is required beacause higher c.r engines the fuel burn rate (here octane rating comes in to picture ) & cylinder pressure rises quickly so you want to retard the ignition to time peak cylinder pressure. now what is this peak cylinder pressure for that look at the diagram below
Its quite obvious that how quickly the cylinder reaches maximum pressure after ignition is determined by the rate at which fuel burns & C.R, in left pic if your peak cylinder pressure occurs at T.D.C the Piston, Rod & Crank are in aligned with the centre line of crank the energy released instead of turning crankshaft rotation is absorbed by block, head, bearings this is no good & very dangerous if your Car is NOS or Turbocharged cause they increase the burn rate of the fuel mix, by having peak cylinder pressure at 12-14 ATDC (right pic) the Rod is at angle with crank centreline when cylinder pressure puts force on piston it spins the crank. So you want max peak pressure at particular degree so that the force is used to turn the crankshaft.
Most street cars with up to half throttle are tuned to run at 14.7:1 air fuel ratio for N.A engines which is also called as Stoich condition which gives maximum fuel economy,it gets richer by approx 13.1 on full throttle, Honda ecu in open loop mode are self monitoring it takes feedback from various sensors learns & adapts, it makes long & short term fuel corrections based on inputs if you advance your distributor it will learn & retard to make up for that ,if your fuel pressure raises & it runs for long it will trim down the fuel supply by reducing injector pulse width.
in your case chetan i would recommend you following things.
> get your ECM Reset first (just unplug the battery & leave it for some time)
> Check your CAM timing is set to factory Spec
> Set your Ignition timing set to factory spec (16-BTDC) pls chk.
> Check the condition of sparkplugs
> Check your intake air temperature sensor if any
> Your Oxygen sensor could be bad
> Check for loose connection in wires/joints or connectors.
> Check for fuel Pressure & all injectors clogged if any
Do tell us more about your car engine Yr ECU (Part # & Code) whats current c.r ? have you opened the engine or any other work & whats current ignition timing is set at, pics would be great.
Rocam