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Truck won’t start after driving through water

Hi I have a 2004 Silverado 1500 and went out hunting today and it has been raining lately so there were a lot of water puddles in the road. I drove through a couple deep water holes that were not avoidable and water splashed up over the engine and the good of the truck, the truck kept running after that I thought I heard it idle a little funny for a few seconds but stopped and kept driving afterwards. We stopped at a spot to set up and shut the truck off after about an hour we came back to the truck and when I tried to start the truck all I had to do was turn the key to the on position (not all the way to the start position) and the starter engaged constantly by itself. The fuse box was completely soaked so I did my best to dry it off and blow it out. Then I removed the starter relay and turned the key on and put the relay back in and then turned the key to the start it and it just turns the engine over now and no start like there is no fuel. When I try bumping the throttle while cranking the engine it spit air out of the intake. Pulled a spark plug out and it was wet from fuel and put it on metal cranked the engine and it has spark. Any ideas why it won’t start and run?

Press the accelerator pedal all the way to the floor, then try cranking engine for 10-15 seconds, repeat 1-2 more times: it will stop delivering fuel to injectors, cranking will still push air through the engine to dry spark plugs.
Release the pedal and try starting as normal.
If you are lucky, it will do.
I would pray you did not get any water in the cylinders - even if it did not hydro-lock now, some connecting rod[s] may be damaged.
I would check the air filter for water to see if water had a chance to enter the air stream.

You have most likely shorted out some systems and blown a fuse or two.

I would have this towed and let it sit in a heated shop/garage so things can dry out.
First I would use compressed air to dry blow out any standing water from the Power distribution box/Fuse box, the spark plug wells, and any other water that you can see puddled. Crank the heat to at least 70 and let it sit 24 hours.

You may need to put a heat lamp on the Power distribution box too. Careful not to melt it.

I would also pull all the plugs while it is drying.
Once everything is dried out crank it over without the plugs for a few revolutions, check for spark, fuel pressure and then try starting it with the plugs back in.



The computer doesn’t stop delivering fuel to the injectors.

The computer cuts the pulse signals in half to the injectors when in the flooded mode.

OP, open the air filter box to see if the air filter is soaked.


Good ideas above. I’d probably try a few things if I had that problem.

  • providing air cleaner is dry, remove all the spark plugs, crank the engine a few times, then let it sit overnight with the spark plugs removed
  • use a hair dryer on low to dry out the wet electrical equipment, especially the high voltage coil packs
  • crank the engine in complete darkness, looking for any sparks jumping around in the engine area.

Sometimes trying start a balky engine will flood the cylinders so much it won’t start no matter how good the spark is. I had that happen on my old VW Rabbit after doing some fuel injection testing. Removing the spark plugs overnight did the trick.