Intermittent start when hot - NOT MAIN RELAY

[ngbeat]

Hello everyone,
I finally got my Beat on the road, however after a few weeks of use, it started giving me a problem.

On hot days or after a (~15min) drive, engine cranks strongly but won't start but starts with a push start. No issues when cold.

Things checked so far during no start:
Main relay: checked on cranking with a test-light / volt-meter, all seems fine
Voltage on battery during cranking: ~11.5V
Spark on plugs: NO
Spark out of coil: NO (Coil is not hot)
ECU to igniter (white wire): Good continuity, reads ~10V
Igniter to coil (blue wire): 12V (car started shortly after and couldn't recreate non-starting)
Injector signal during cranking: OK
Sensor voltage during cranking: Cyl : 2.4V, TDC: 0.8V (car started shortly after and couldn't recreate non-starting)
Cooling temp sensor to ECU: gives correct resistance values when hot (High ohm when cold, ~200ohm when hot)

On normal operation, CEL is always on, no blinking if diagnosed. Engine runs perfectly and doesn't stall or lose power even if stuck in traffic etc.

Also, Most of the ECU electrolytic capacitors have been replaced and Main relay re-soldered.

Strange thing that car start with a slight push start.

What else can I diagnose? :confused:

[Seventynine]

no spark or weak spark?

hot starting issues are nearly always due to a weak ignition system, have you replaced leads/plugs/rotor arm?

[ngbeat]

no spark .. both at spark plugs and at coil (before distributor)

so far I haven't replaced anything .. car drives fine no mis-firing or whatsoever .. plugs are clean when checked

strangest thing is it start with a bump start :confused:

[Seventynine]

i'd still stand by my statement, plugs/leads/rotor arm are all service items so should be replaced as per the service schedule (or thereabouts) i'd imagine yours being sat up for so long is in desperate need of them swapping

if you still have an issue at least you're working with a "good" ignition system

[ngbeat]

excuse my "ignorance", but if any part of the ignition system is weak .. won't it affect driving / idling and maybe cause the car to stall?

Car drives great and upon inspection of plugs, color shows good mixture etc and it never stalled.

[Seventynine]

not quite, starting is a worst case condition for spark as there's not much fuel or air in the cylinder (hotter temps = lower VE, low engine speed = lower VE) which will cause it to struggle to ignite.

the plugs will look fine because once the engine is running the boundary conditions are adequate for successful ignition.

[CZski]

I have the same issue with hot starts

[Sharpen]

I had same whereby it would stall after around 15 mins and then not start again. Turned out to be the air control valve. Like this:
http://www.ebay.co.uk/itm/HONDA-BEAT-PP1-ELECTRONIC-AIR-CONTROL-VALVE-ASSY-36450-P36-004-EACV-JDM-MINI-CAR-/201162619153?hash=item2ed639f911:g:Xe4AAOSwGYVW~ao s

If it sticks then the engine it starved of enough air tho start (when hot), guess it's a known fault if they're available on like on eBay.