Why Won't My Car Start When It Rains?


11 Answers

asssss ddaaaa Profile
asssss ddaaaa answered
Usually the cause of a no start in rain/high humidity conditions is that the spark voltage is arcing to the engine metal rather that to the spark plug because of worn out spark plug wire insulation. You may be able to observe this when the engine is running at night in a dark location when it is wet outside by opening the hood and observing for arcs jumping out from the spark plug wires. The distributor cap could also be cracked which can also short the voltage to ground. So my first suggestion is to replace the spark plug wires and look carefully at the distributor cap for any signs of a crack.
thanked the writer.
eugene hunt
eugene hunt commented
Had that problem on my wife's car, new spark plug wires and coil wire fixed it. Be sure to wipe any grime off of the coil and distributor cap while you are in there.
Anonymous Profile
Anonymous answered
I read the blog about using Wd-40 and it works,just tryed it.Spray the cap and the wires and car starts right up .I have 1996 honda accord.Total cost $1.69
Anonymous Profile
Anonymous answered
Its either your cap and/or rotor or, your main relay. If you replace those and it does not help, my advice would be to take it to a shop. Otherwise your going to be spending a lot of  money on suggestions.

: P.s in my professional opinion ( I am a master mechanic ) Dielectric grease is a far
Anonymous Profile
Anonymous answered
Like I was saying Dielectric grease is a far better choice than WD-40
Tara Tompkins Profile
Tara Tompkins answered
Hey my car does the same thing. Its an 89 volvo 740gl, the reason why mine does it is because there is a leak in one of the plugs on the bottom of my distributor cap and so the oil shoots into the distributor cap. When that happens the oil sucks in the moisture from the rain and causes the sparks to misfire. :)
John Profile
John answered
Spark gap being prevented by moisture in the distributor cap or between the points.
larry cook Profile
larry cook answered
Need to check the rotor cap it might be cracked an letting moister in you can take cap off an put baby power in it to see if is cracked
Anonymous Profile
Anonymous answered
I own a 1990 honda accord. Lately when it rains it will not start. Right after it clears up the car will start. My mechanic seems to think it is a relay. What else can it be?
Anonymous Profile
Anonymous answered
All of these answers are fine and dandy but what if I need to use my car like... Now!? Doesn't anyone have a quick fix to dry it out, like something with a hairdryer?
Sarah jessica Profile
Sarah jessica answered
The dilemma is highly simple. Your car doesn't start when it rains because the rain water gets into the silencer of your car. When this happens, no car starts functioning. Nothing much is wrong with you car so absolutely no worries.

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