Hello peeps. New here, and usually I don’t ask for advice, but hopefully this hits someone’s interest.

I’m working on my nieces Honda and we’ve done a lot to fix it:
new fuel pump assembly
new fuel injector o-rings, Cleaned swapped and tested injectors.
new intake manifold gaskets
new air filter
cleaned the clogged EGR vanes on the intake
new EGR and gasket
new plugs and Coils, confirmed ecu signal to coil as good.
new timing belt kit with water pump, triple checked timing.
new cam pos sensor
new crank pos sensor
Compression tested at ~225psi on all cyl
leakdown tested at 95%+ on all cyl

confirmed grounds and updated bonding straps.
replaced ELD
checked fuses.

my current problem is that it long starts on cold days, and continues to throw a P0302 (and occasionally P0301)
coil voltage min/max under static load is:
1 -.368-4.812 (P0301)
2 -.282-4.772 (P0302)
3 -.423-4.779
4 -.375-4.751

any ideas?

 

Quick update: I reset the PCM/ECU to clear the memory in the hopes that the #2 ignition coil min/max averages would be reset to the new ignition coil. So far it’s been starting normally and no codes, I’ll update if any codes get thrown.

 

Vehicle is back, had a crank no start in cold temp (15F).

no DTCs (trouble codes), however scan tool indicates multiple misfires on cylinders 1, 2, and 3, just not setting a code.

Put it in the garage overnight, long started the next morning, ran rich for a minute. Personally, I think this indicates plenty of fuel given the previous repairs.

searching the forums, I saw an ECT (engine coolant temp sensor) could be providing bad info to the ecu, but no faulty ECT indications were found during run up and idle. Engine starts perfect after it’s warm.

also, checking for faulty catalytic converter, I checked back pressure at the #1 o2 sensor, shows little to no back pressure.

currently running an injector leakdown test for a leaky injector, which could be flooding the cylinder(s) overnight, exacerbated by cold temps. Always open to ideas if anyone out there has any...

 

Check fuel injectors and valve clearances.

 

thanks for the reply!

so I’ve cleaned the injectors with injector kleen and replaced the o rings, is there something I’m missing that could cause them to only fail in cold temps while still flooding the cylinders?

and I haven’t adjusted the valves, but during the timing belt change they weren’t outrageously loose and they don’t tap when it’s idling normally. Would that small adjustment be enough to prevent a start only during cold starts?

an additional point of info is that the car will start if it’s been left on a freeze plug heater overnight.

thanks again!