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i have this strange problem where my car normally starts just fine in 3 cranks, but when i park the car and a storm system moves in, later the car does not start at all. it just keeps cranking and after 10 times i wait and try again. usually after several tries, it finally stumbles and turns over. is the ecu remembering old pressure readings and getting confused by a sudden drop in atmosphere? other times on sunny days the car starts fine all the time and also drives normally... ive also noticed that if i take off the air intake, the engine takes longer to start the first time. so maybe its a sensor problem where the car expects certain conditions to remain the same.

 
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I don't think thats the issue. Your still getting 14.7 psi of Oxygen no matter what (unless it's colder out side) I've never had an issue like that and I live in Maine. The weather changes ALL the time here. try this. The next time it won't start reset your computer. Then see if it'll start back up. If it fires up right away then it could be the ECU. Remember when I was having my issues a while back? Kind of the same thing.

 
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yeah its possible. it may also be hot-cold air changes but idk. its just strange that its never happened before unless the clouds start rolling in.

 
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Strangest problem I've ever heard. I don't know the climate in reno, but does the humidity spike when there is a storm coming? It does here usually. Not sure if that would have anything to do with it, just throwing something out there.

 
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What about you Barometeric sensor? Don't these civic's have one of these? Also maybe it's a bad ground or something?

 
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lol well baro pressure drops with a storm, also it goes from 10% to 90% humidity. maybe combined factors or something. grounds are all good.

 
Rep Power: 317

wow I never thought I would see Gearbox asking for help, he's like God on this board.

Actually, I also have an issue sort of like this now that I'm up in WA state. When it rains and I get on the freeway, it seems like my engine bogs down a bit and I don't get much acceleration compared to being in clear conditions. Doesn't happen all the time though.

 
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mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm This ones a stumper. Let me get the facts right

When rain is coming it bogs down
you have Zero grounding issues
and really that's all we know. Judging by your knowledge I don't need to bring in dumb things because you already know about it.

SOOOOOO

Are you getting any check lights (I'll say know because you would have said so)?
Has this issue EVER happened and it not rain?
Do you know this is due to that reason? For example, theres a low pressure front moving in.

Is there any thing that is causing your engine NOT to go into closed loop? Mods and such.
Does you engine run strange while running?

The ECU/PCM is designed to "learn" the weather conditions and such hense the "barometeric" pressure sensor. How ever if a motor is run under the same condition over a long period of time it will run those settings and loop them.
Have you reset your computer to rule that out?
Did you do the above in the first post that I did?

ok with all of that out of the way lets think of the cold starting circuit and such. Whats related on the D17 that could cause an issue with "cold starting"?

 
Rep Power: 811

no check lights, issue never happens on clear sunny (or mild cloudy) days. only happens if i drive the car in clear skies, park it, then a storm system comes in with overcast and colder temps (doesnt matter if its raining or not). after the storm moves in and car has trouble starting the first time, after that it starts up like normal, even if its raining. i know theres a map sensor which measures air pressure, maybe its going bad? i plan to change the plugs soon since its time, but there is no indication they are really to blame. car starts normally in good weather and never misses while driving. also once the car finally stumbles on, it runs fine after that like nothings wrong.

 
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if it was your MAP then your car would run super rich and would stumble while idling.

 
Rep Power: 313

I wonder if the humidity is screwing with your coil packs or something. I hear this is a common problem on cars that have dizzys. The coil pack and wires soak the humidity in and it loses spark to the plugs. Generally the treatment is new cap/rotor/wires/plugs but on our cars half that is eliminated anyway. Next time you suspect the issue maybe try checking to see if you have spark? Only you can have a problem like this lol.