Skip the auto shop - Our mechanics make house calls

Q: How Does Water Get Into a Car's Ignition System?

asked by on

How does water get into a car's ignition system?

Depending on what type of ignition system you have, a conventional older style ignition system with a distributer cap and ignition rotor, or a more updated version on newer vehicles that has a coil per spark plug, there are several ways for water to get in. In most cases, rain or hitting a deep puddle will be the cause of water issues.

There is no stopping mother nature. Sometimes getting water into your engine compartment is inevitable, even though the ignition systems are supposed to be sealed so that water cannot affect it.

You could possibly have a cracked distributor cap or a missing gasket between the distributor housing and the plastic cap. If this is the case, water could get in and make the car misfire, buck, and cause a lot of running and starting issues.

If you have the coil on spark plug design there is no reason for water to affect it unless the coil is cracked and needs to be replaced.

Sometimes it’s possible to get excessive water into the engine compartment due to a technician error. Most of newer vehicles have long plastic shields under the engine compartment that are there to stop water from getting to the top of the engine, unfortunately some technicians have to take these off to perform routine service on the vehicle and forget to put them back on. Also, the owner of the vehicle can run something over and destroy this protective cover which people end up removing.

Check to see if your vehicle is supposed to have the shields that could possibly be missing if you are having running issues due to wet weather or puddles. If you ever run into any issues with your ignition system, feel free to contact a certified mechanic who can diagnose your starting problems and make the necessary repairs to get you going again.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. How Does Water Get Into a Car's Ignition System?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: I pulled too close to a concrete parking stall and scraped the bottom of the front bumper. What type of damage should I look for?

Hello. The extent of damage you should be looking for is relative to how hard that concrete blocker with hit/scraped. Its dificult to say which parts may have been effected without knowing where exactly the vehicle was hit. The radiator...

Q: Van won't start it turns I change out fuel pump, coil & got tested on the module

If you are not getting spark from the coil then you will need to test for ignition power on one side of coil and crank signal on the other side. If you have no signal to coil then check the...

Q: Key locked in ignition

Hi. Your vehicle is equipped with a key interlock system that keeps the key from coming out unless the vehicle is put fully into park. You need to see if the key will come out if the shifter is pushed...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...