Hard start in cold weather

[rekvy]

Hello all,
did someone have the same hard start problem like me? It happens only in the morning when the engine is very cold. It starts but stalls right away, second try is all ok. Sometimes the engine starts the first time but RPM goes all crazy bouncing from 500 to 2000 and then after 3 sec settle to normal 1500 and then runs as it should. However when engine is warm the car starts right up at first try. Do you think it could be bad valve clereance (I think it has never been done)? I also suspect fuel injectors and ignition coils, but the car starts normal when warmed up and runs perfect so not sure about that...No engine code present.
What i did to my car but didn't affect this problem:
-new battery
-new temp sensor
-injector cleaner (additives to fuel)
-different fuel pump
-new spark plugs
- map and crank sensor cleaning
- new air filter and oil

I think it could be the bad valve clereance, what do you think? I also can hear little ticking or little tapping noise when engine is cold from engine department and another symptom is that engine is little bit shaking when warmed up
Thank you

[coldstart]

 Have you considerd having it looked over by an official Honda garage?

[madasafish]

Clean EGR valve.

[rekvy]

it has never been in official honda dealership  I think I'm going to pass on that since the car is old and has more than 100k miles. Probably inspection would be more expensive than the car
EGR valve and egr passages was cleaned less than 1000 miles ago...

[Westy36]

I might be tempted to change a coil over from one cylinder to another and see what happens. Have you had a look at them to see if there is any cracking or the electrical connections are in decent condition. You've crossed a lot of things off the list, so not sure.

What code reader are you using? A proper diagnostic, Snap on etc, might find codes a basic reader can't. Might be worth having a chat with a local garage or two and see if they will offer a friendly rate for a more detailed diagnostic check.

[rekvy]

thanks. Coil pack was checked when I've changed spark plugs and there was no visual damages. But it could be spark plugs, who knows. However it's weird that bad first start happens only when car stands for more that 8 hours and outside temperature is below 12°C. Otherwise it works all good, no power loss..
I have some basic diagnostic tool, nothing professional... I might take it to some local garage to see their opinion...

[madasafish]

Sounds like a sensor failures: classic symptoms.
Crankshaft sensor? So no spark?
You need to do/get a systematic checking out of electrical system  when it will not start.

[embee]

The way all the dash lights dim or go out when it cranks would suggest to me that the battery might be tired. I know tired batteries would cause stalling after start in some older cars because the voltage recovery after crank and fire could be outside the expected range for the engine ECU and voltage correction values wouldn't cope.
Worth checking the charging system and/or age of the battery.
(Edit .. just noticed you say new battery).

[coldstart]

it has never been in official honda dealership

You could always ask for a cost estimate and decide aftwards. (the estimate may cost a few quid but might help you find the root cause of what's wrong with your car)

[rekvy]

I tried to swap the ignition coils (2 to 1 and 3 to 4 both sides) and no effect on bad starts... Also try tu unplugged them while engine was running and I could say all coils are ok...

[embee]

Have you watched what the battery voltage drops to during cranking and how quickly it recovers once running?

[rekvy]

I think it's not battery, because I tried to start it with connected powerbank jumpstarter without any difference...
Anyway I can see some changes after swapping coils, so maybe one or two coils are slowly dying. The car starts much better now and sometimes in first try. I need to measure it first and let you know the results... Thanks.

[rekvy]

So the problem has been solved by replacing the rear coils. The car starts right up. Thank you all for help